Second domain trouble - firs domain work correctly

I have trouble with addition of second domain. Everything looks good, but when I go to webmail there is problem with outgoing messages - it is not able to save outgoing email into folder, and roundcube send me this alert:

“Chyba serveru: STATUS: Internal error occurred. Refer to server log for more information. [2026-05-12 19:47:26] (0.002 + 0.000 + 0.001 secs).” Chyba serveru means - sever fail.

[12-May-2026 19:51:38 +0200]: <rttgnc55> IMAP Error: Could not save message in Sent in /usr/local/lib/roundcubemail/program/include/rcmail_sendmail.php on line 575 (POST /mail/?_task=mail&_unlock=loading17786082
98037&_framed=1&_action=send)

[13-May-2026 10:57:08 +0200]: <n6rngiff> IMAP Error: Login failed for atmadm@atmex.group against localhost from 80.95.112.249. AUTHENTICATE PLAIN: Authentication failed. in /usr/local/lib/roundcubemail/program/l
ib/Roundcube/rcube_imap.php on line 211 (POST /mail/?_task=login&_action=login)

And here is list of directories of second mail:

    3517 atmex.group/atmadm/cur/1778608968.M312510P1940587.box.ludacka.net,S=3517,W=3594:2,RSa
    3839 atmex.group/atmadm/cur/1778617169.M667562P1961127.box.ludacka.net,S=3839,W=3932:2,S
    3881 atmex.group/atmadm/cur/1778617847.M254597P1963516.box.ludacka.net,S=3881,W=3979:2,Sa
    2315 atmex.group/atmadm/cur/1778662693.M96508P114010.box.ludacka.net,S=2315,W=2369:2,Sa
      10 atmex.group/atmadm/dovecot-keywords
     289 atmex.group/atmadm/dovecot-uidlist
       8 atmex.group/atmadm/dovecot-uidvalidity
       0 atmex.group/atmadm/dovecot-uidvalidity.6a036594
    3100 atmex.group/atmadm/dovecot.index.cache
    2288 atmex.group/atmadm/dovecot.index.log
     400 atmex.group/atmadm/dovecot.list.index.log
      35 atmex.group/atmadm/maildirsize

I thing here is problem with acces to new directory, because directories of first mail are correct.

I would like to ask how i can solve this problem?

Thank you for any help.