diff --git a/backend/serverless.yml b/backend/serverless.yml
index c097efdf..125d626a 100644
--- a/backend/serverless.yml
+++ b/backend/serverless.yml
@@ -31,7 +31,7 @@ custom:
   customDomain:
     domainName: api-${self:provider.environment.ENVIRONMENT}.${self:provider.environment.DOMAIN_NAME}
     createRoute53Record: true
-    certificateArn: ${ssm:/ssl_certificate_arn~true}
+    certificateArn: ${ssm:/ssl_certificate_arn}
 
 functions:
   app: