I have zoho mail IMAP set up on laptop and iPhone.  I continually get asked for password on iPhone.  If I close the outlook app and reopen, then no password needed and emails update but soon after, I get another request for password on this account.  I've changed password and deleted zoho mail and set up from scratch and still it happens.  Switched phone on and off too.  This problem has been reported by me previously but response to reset password didn't help.  There are LOTS of other people having this same problem.  Please zoho mail what's the answer?  This isn't acceptable!