If I want remote users to connect to their mailbox only using separate IMAP proxy. Is it possible with IMAP proxy to connect backend Zimbra server?

Do I need to change anything in Zimbra configuration to accept user authentication request via separate IMAP proxy server using NGINX? I'd appreciate if you could share some resource or guides to accomplish this.

I have configured nginx.conf but no logs I am getting for user failed authentication. Every time user is trying to connect to backned server authentication via IMAP proxy, authentication is failed.

I am getting this message in thunderbird client application: authentication failed and "The server may have gone down or there may be a network problem"