Connection closed (user disabled)

Hello everyone

Thank you in advance for your help.

Why do I get the following error:

Aug 23 10:37:51 cp-cl02 dovecot[2337577]: pop3-login: Disconnected: Connection closed (user disabled): user=<loliva@romaseguro.pe>, method=PLAIN, rip=x.x.x.x, lip=x.x.x.x, TLS: Connection closed, session=<8na4jlsg3HK1Q1LE>.

I never observed this before: Connection closed (user disabled):

I wish to know what is causing it and how can I fix it.

Thank you.