diff --git a/src/Bundle/ChillPersonBundle/Tests/Validator/Person/BirthdateValidatorTest.php b/src/Bundle/ChillPersonBundle/Tests/Validator/Person/BirthdateValidatorTest.php
index 98810db95..ba4e7b27b 100644
--- a/src/Bundle/ChillPersonBundle/Tests/Validator/Person/BirthdateValidatorTest.php
+++ b/src/Bundle/ChillPersonBundle/Tests/Validator/Person/BirthdateValidatorTest.php
@@ -28,7 +28,7 @@ final class BirthdateValidatorTest extends ConstraintValidatorTestCase
 {
     public function testTomorrowInvalid()
     {
-        $bornAfter = new DateTime('+2 days');
+        $bornAfter = new DateTime('2023-08-31');
         $this->validator->validate($bornAfter, $this->createConstraint());
         $this->buildViolation('msg')
             ->setParameter('%date%', (new DateTime('2023-08-29'))->format('d-m-Y'))
@@ -38,7 +38,7 @@ final class BirthdateValidatorTest extends ConstraintValidatorTestCase
 
     public function testValidateTodayInvalid()
     {
-        $bornToday = new DateTime('now');
+        $bornToday = new DateTime('2023-08-30');
         $this->validator->validate($bornToday, $this->createConstraint());
         $this->buildViolation('msg')
             ->setParameter('%date%', (new DateTime('2023-08-29'))->format('d-m-Y'))
@@ -59,7 +59,7 @@ final class BirthdateValidatorTest extends ConstraintValidatorTestCase
 
     public function testValidateYesterdayValid()
     {
-        $bornYesterday = new DateTime('yesterday');
+        $bornYesterday = new DateTime('2023-08-29');
         $this->validator->validate($bornYesterday, $this->createConstraint());
         $this->assertNoViolation();
     }