Bitbucket Cannot connect to Proxy error

During the oauth flow while onboarding a new app, I am getting a proxy error saying unable to connect to proxy with http status code 403. It retries and fails.

HTTPSConnectionPool(host=‘api.domain.com’, port=443): Max retries exceeded with url: /api/apps/endpoint (Caused by ProxyError(‘Cannot connect to proxy.’, error(‘Tunnel connection failed: 403 Forbidden’,)))", “error”=>“server_error”, “provider”=>“bitbucket”}

However, both the backend and the proxy don’t show any logs or any trace that event has reached till my endpoint/proxy.

Any ideas on what could be the issue. I see a similar ticket already logged but it didn’t help much and it doesn’t even have root cause mentioned in the answer.

Thanks

is your domain in AWS region us-east-1? If so change to a different region and problem goes away.