This has been a issue for several weeks now, i noticed on the forum it was posted you said the problem was your side and it should be fixed now. But im still having the same issue. I have re-enabled password etc but its still happening.
We
would like to acknowledge that there was an internal breakage while
performing the authentication checks for the external accounts that were
configured as POP3 within Zoho Mail client. Due to this breakage, users
must have noticed repeated authentication errors & notifications on
the getting disabled from further mail fetching. Our backend team had identified the root cause of the issue, made the necessary changes and fixed it.