diff --git a/Tests/Functional/SequenceTest.php b/Tests/Functional/SequenceTest.php
index 4fb3067..b912129 100644
--- a/Tests/Functional/SequenceTest.php
+++ b/Tests/Functional/SequenceTest.php
@@ -23,7 +23,7 @@ class SequenceTest extends FunctionalTestCase
      * @throws DoctrineDBALException
      * @throws InvalidSourceException
      */
-    public function sequenceTest()
+    public function sequenceTest(): void
     {
         $sequenceGenerator = $this->objectManager->get(SequenceGenerator::class);
 
@@ -58,7 +58,7 @@ class SequenceTest extends FunctionalTestCase
      * @throws DoctrineDBALException
      * @throws InvalidSourceException
      */
-    public function setLastNumberForTest()
+    public function setLastNumberForTest(): void
     {
         $sequenceGenerator = $this->objectManager->get(SequenceGenerator::class);