Authorization by IMAP is failed

Good day to all!

There is Postfix + Dovecot mail server. Authorization by IMAP for login and password. Email clients connect and work.
When I configure the connection in SuiteCRM I get the error “Invalid login or password”.
The SMTP connection is configured and running.
In the server logs such messages:

Jun 26 15:42:29 server dovecot: imap-login: Aborted login (client did not finish SASL auth, waited 0 secs): user = <>, method = GSSAPI, rip = YYYY, lip = XXXX, session = < 7 / 7K1Ipv / ADAqAAz>
Jun 26 15:42:29 server dovecot: imap-login: aborted login (no auth attempts in 0 secs): user = <>, rip = Y.Y.Y.Y, lip = X.X.X.X, session = <90bL1Ipv / gDAqAAz>
Jun 26 15:42:29 server dovecot: imap-login: aborted login (no auth attempts in 0 secs): user = <>, rip = Y.Y.Y.Y, lip = X.X.X.X, session =

Tell me, please, how to change the authentication method in SuiteCRM !!!

Anyone fix this?