One of my mail users is setup to simply forward all mails to two other email addressees (zen and gmail).  However one of these (zen) is rejecting any spam with bounce messages which in turn is causing zoho to disable the mail forwarder.

Is there anything I can do in zoho mail to help solve this problem please?

I've sent an email to support [at] zohomail.com and logged a ticket with the support centre but both have been ignored.

Thanks for your help.