diff --git a/symfony/mailer/4.3/config/packages/mailer.yaml b/symfony/mailer/4.3/config/packages/mailer.yaml
index 56a650d89..e62b31e7a 100644
--- a/symfony/mailer/4.3/config/packages/mailer.yaml
+++ b/symfony/mailer/4.3/config/packages/mailer.yaml
@@ -1,3 +1,3 @@
 framework:
     mailer:
-        dsn: '%env(MAILER_DSN)%'
+        dsn: '%env(resolve:MAILER_DSN)%'