Atlas peering connection cannot resolve the Atlas hostname to private address

Hi, we are using serverless version Atlas and tha work well on public ip system.
recently we need to use our AWS ECS to access our Atlas by peering connections, so we followed document and created peering connections. we have enabled DNS hostname and DNS resolution on our VPC, also added route table for peering connection. but after all settings we cannot see the Atlas hostname in connection string been resolved to private ip address.
We followed this document:
But in our VPC EC2 the standard connection strings will resolved to public ip
if we use ‘-pri’ format connection string then the hostname cannot resolved.
(we have already toggle the ‘Using Custom DNS on AWS with VPC Peering’ on On from the Project Settings menu)
What we can do for using peering private connections.

found the answer here:
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