diff --git a/dev/tests/functional/tests/app/Magento/Braintree/Test/Constraint/AssertTransactionIsPresentInSettlementReport.php b/dev/tests/functional/tests/app/Magento/Braintree/Test/Constraint/AssertTransactionIsPresentInSettlementReport.php
index 1a8f35587e5f3f9f94d60302da11a920c067b006..434e41bb50023a6680ccdef448515edbe8007911 100644
--- a/dev/tests/functional/tests/app/Magento/Braintree/Test/Constraint/AssertTransactionIsPresentInSettlementReport.php
+++ b/dev/tests/functional/tests/app/Magento/Braintree/Test/Constraint/AssertTransactionIsPresentInSettlementReport.php
@@ -70,9 +70,9 @@ class AssertTransactionIsPresentInSettlementReport extends AbstractConstraint
     }
 
     /**
-     * Get transaction id from order comments
+     * Get transaction id from order comments.
      *
-     * @return mixed
+     * @return null|string
      */
     private function getTransactionId()
     {
diff --git a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertAcceptPaymentMessageInCommentsHistory.php b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertAcceptPaymentMessageInCommentsHistory.php
index 0b041c8c119528eb372c43e4756c36898dd2be17..d9c75b3c9dad045109306e816838602026e1c012 100644
--- a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertAcceptPaymentMessageInCommentsHistory.php
+++ b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertAcceptPaymentMessageInCommentsHistory.php
@@ -10,7 +10,7 @@ use Magento\Sales\Test\Page\Adminhtml\OrderIndex;
 use Magento\Sales\Test\Page\Adminhtml\SalesOrderView;
 
 /**
- * Assert that accept payment message exist in Comments History section on order page in Admin.
+ * Assert that accept payment message exists in Comments History section on order page in Admin.
  *
  */
 class AssertAcceptPaymentMessageInCommentsHistory extends AbstractConstraint
@@ -23,7 +23,7 @@ class AssertAcceptPaymentMessageInCommentsHistory extends AbstractConstraint
     private static $message = 'Approved the payment online.';
 
     /**
-     * Assert that accept payment message exist in Comments History section on order page in Admin.
+     * Assert that accept payment message exists in Comments History section on order page in Admin.
      *
      * @param SalesOrderView $salesOrderView
      * @param OrderIndex $orderIndex
diff --git a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertAuthorizationInCommentsHistory.php b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertAuthorizationInCommentsHistory.php
index 13ceba996e989060550f4418437d001c97e29637..309a3795e68ab84398d623476a00939c405bf51f 100644
--- a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertAuthorizationInCommentsHistory.php
+++ b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertAuthorizationInCommentsHistory.php
@@ -21,7 +21,7 @@ class AssertAuthorizationInCommentsHistory extends AbstractConstraint
     const AUTHORIZED_AMOUNT_PATTERN = '/(IPN "Pending" )*Authorized amount of \w*\W{1,2}%s. Transaction ID: "[\w\-]*"/';
 
     /**
-     * Assert that comment about authorized amount exist in Comments History section on order page in Admin.
+     * Assert that comment about authorized amount exists in Comments History section on order page in Admin.
      *
      * @param SalesOrderView $salesOrderView
      * @param OrderIndex $salesOrder
diff --git a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertCaptureInCommentsHistory.php b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertCaptureInCommentsHistory.php
index 5ca9c6ef9bc5600619f99ef81505a296152656df..14379c279fedcfde5a8ff60eed82a48e102a5fae 100644
--- a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertCaptureInCommentsHistory.php
+++ b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertCaptureInCommentsHistory.php
@@ -22,7 +22,7 @@ class AssertCaptureInCommentsHistory extends AbstractConstraint
     const CAPTURED_AMOUNT_PATTERN = '/^Captured amount of \w*\W{1,2}%s online. Transaction ID: "[\w\-]*"/';
 
     /**
-     * Assert that comment about captured amount exist in Comments History section on order page in Admin.
+     * Assert that comment about captured amount exists in Comments History section on order page in Admin.
      *
      * @param SalesOrderView $salesOrderView
      * @param OrderIndex $salesOrder
diff --git a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertDenyPaymentMessageInCommentsHistory.php b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertDenyPaymentMessageInCommentsHistory.php
index 8e95790dd857a3cb75e12c8042dee5240bcc0b42..1fca0cc18869d4b5f1e0240119fee774596a46ab 100644
--- a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertDenyPaymentMessageInCommentsHistory.php
+++ b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertDenyPaymentMessageInCommentsHistory.php
@@ -10,7 +10,7 @@ use Magento\Sales\Test\Page\Adminhtml\OrderIndex;
 use Magento\Sales\Test\Page\Adminhtml\SalesOrderView;
 
 /**
- * Assert that deny payment message exist in Comments History section on order page in Admin.
+ * Assert that deny payment message exists in Comments History section on order page in Admin.
  *
  * Constraint checks deny payment message in order comments history
  */
@@ -24,7 +24,7 @@ class AssertDenyPaymentMessageInCommentsHistory extends AbstractConstraint
     private static $message = 'Denied the payment online';
 
     /**
-     * Assert that deny payment message exist in Comments History section on order page in Admin.
+     * Assert that deny payment message exists in Comments History section on order page in Admin.
      *
      * @param SalesOrderView $salesOrderView
      * @param OrderIndex $orderIndex
diff --git a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertRefundInCommentsHistory.php b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertRefundInCommentsHistory.php
index 5b035fc420a533fbc04f39029ceb29b7d0ca3963..db16052ed107f1d8196cfb89f409134832d5f971 100644
--- a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertRefundInCommentsHistory.php
+++ b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertRefundInCommentsHistory.php
@@ -21,7 +21,7 @@ class AssertRefundInCommentsHistory extends AbstractConstraint
     const REFUNDED_AMOUNT_PATTERN = '/^We refunded \w*\W{1,2}%s online. Transaction ID: "[\w\-]*"/';
 
     /**
-     * Assert that comment about refunded amount exist in Comments History section on order page in Admin.
+     * Assert that comment about refunded amount exists in Comments History section on order page in Admin.
      *
      * @param SalesOrderView $salesOrderView
      * @param OrderIndex $salesOrder
diff --git a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertRefundOrderStatusInCommentsHistory.php b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertRefundOrderStatusInCommentsHistory.php
index c6f72f427d04119a33da3a04afc73c2cfdf2cd2f..c90bbf68531cc02ad558bbe259ac74562facab82 100644
--- a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertRefundOrderStatusInCommentsHistory.php
+++ b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertRefundOrderStatusInCommentsHistory.php
@@ -11,12 +11,12 @@ use Magento\Mtf\Constraint\AbstractConstraint;
 use Magento\Sales\Test\Fixture\OrderInjectable;
 
 /**
- * Assert that comment with correct order status exist in Comments History section on order page in Admin.
+ * Assert that comment with correct order status exists in Comments History section on order page in Admin.
  */
 class AssertRefundOrderStatusInCommentsHistory extends AbstractConstraint
 {
     /**
-     * Assert that comment with correct order status exist in Comments History section on order page in Admin.
+     * Assert that comment with correct order status exists in Comments History section on order page in Admin.
      *
      * @param SalesOrderView $salesOrderView
      * @param OrderIndex $salesOrder
diff --git a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertVoidInCommentsHistory.php b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertVoidInCommentsHistory.php
index 1b9c48fdc4ab973c55b615ab1528582bbbf68fbb..b3df74ea74a20696c2ee0e7fc9de6c0fce4b84c5 100644
--- a/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertVoidInCommentsHistory.php
+++ b/dev/tests/functional/tests/app/Magento/Sales/Test/Constraint/AssertVoidInCommentsHistory.php
@@ -21,7 +21,7 @@ class AssertVoidInCommentsHistory extends AbstractConstraint
     const VOIDED_AMOUNT = 'Voided authorization. Amount: $';
 
     /**
-     * Assert that comment about voided amount exist in Comments History section on order page in Admin.
+     * Assert that comment about voided amount exists in Comments History section on order page in Admin.
      *
      * @param SalesOrderView $salesOrderView
      * @param OrderIndex $salesOrder