HELP - Cannot access my zoho mail in Gmail app - Android N

HELP - Cannot access my zoho mail in Gmail app - Android N

I've more than triple-checked my username and password, changed my password to be sure (organisation: user@customdomain, not user@zoho,eu)

The same credentials work fine in Mozilla Thunderbird on both windows and mac

I'm using the following server settings:

imappro.zoho.eu
Port 993
SSL/TLS

TFA is not active on my domain

it just flat out refuses to let me in- HELP!