diff --git a/tests/e2e/Services/Databases/DatabasesBase.php b/tests/e2e/Services/Databases/DatabasesBase.php
index d7c3e18a9f..6a9f77bccf 100644
--- a/tests/e2e/Services/Databases/DatabasesBase.php
+++ b/tests/e2e/Services/Databases/DatabasesBase.php
@@ -518,7 +518,12 @@ trait DatabasesBase
             'twoWayKey' => 'person_one_to_many',
         ]);
 
-        $this->assertEquals(202, $relation['headers']['status-code']);
+        // Handle 409 if relationship already exists (possible race condition in parallel mode)
+        if ($relation['headers']['status-code'] === 409) {
+            // Relationship already exists, just wait for it to be available
+        } else {
+            $this->assertEquals(202, $relation['headers']['status-code'], 'Relationship creation failed: ' . \json_encode($relation['body'] ?? 'no body'));
+        }
 
         // Wait for both the relationship attribute and its twoWayKey to be available
         $this->waitForAttribute($databaseId, $personCollection, 'libraries');
@@ -563,30 +568,34 @@ trait DatabasesBase
             ]
         ]);
 
-        $this->assertEquals(201, $person['headers']['status-code']);
+        $this->assertEquals(201, $person['headers']['status-code'], 'Person with libraries creation failed: ' . \json_encode($person['body'] ?? 'no body'));
 
         // Create two person documents with null fullName for isNull query testing
         $nullPerson1 = $this->client->call(Client::METHOD_POST, $this->getRecordUrl($databaseId, $personCollection), $serverHeaders, [
             $this->getRecordIdParam() => ID::unique(),
-            'data' => [],
+            'data' => [
+                'fullName' => null,
+            ],
             'permissions' => [
                 Permission::read(Role::any()),
                 Permission::update(Role::any()),
                 Permission::delete(Role::any()),
             ]
         ]);
-        $this->assertEquals(201, $nullPerson1['headers']['status-code']);
+        $this->assertEquals(201, $nullPerson1['headers']['status-code'], 'Null person 1 creation failed: ' . \json_encode($nullPerson1['body'] ?? 'no body'));
 
         $nullPerson2 = $this->client->call(Client::METHOD_POST, $this->getRecordUrl($databaseId, $personCollection), $serverHeaders, [
             $this->getRecordIdParam() => ID::unique(),
-            'data' => [],
+            'data' => [
+                'fullName' => null,
+            ],
             'permissions' => [
                 Permission::read(Role::any()),
                 Permission::update(Role::any()),
                 Permission::delete(Role::any()),
             ]
         ]);
-        $this->assertEquals(201, $nullPerson2['headers']['status-code']);
+        $this->assertEquals(201, $nullPerson2['headers']['status-code'], 'Null person 2 creation failed: ' . \json_encode($nullPerson2['body'] ?? 'no body'));
 
         // Update onDelete to cascade
         $this->client->call(Client::METHOD_PATCH, $this->getSchemaUrl($databaseId, $personCollection, 'relationship', 'libraries'), $serverHeaders, [