CloudFormation does not check whether rds proxy target groups are created.

I am working on infrastructure distribution through cdk, but the target group of rds proxy does not change from creation to completion for more than 50 minutes.

I checked and found that the resource was already created, so Cloudformation did not confirm the completion of the creation.

The target rds database is created together in cdk and is aurora serverless v2 (mysql).

How can I solve this?