Mail Fetch not working with GMAIL

Zoho Mail stopped working with my GMAIL account. After suffering through several weeks of it downloading my mail at about 20-25 email per 5 minutes, it stopped at about 125K email. Zoho first said this was all a problem with Google GMAIL. Finally got both on line in conference call. Google demonstrated that (1) it was not a GMAIL problem (e.g., I can create a POP account in Microsoft Outlook 2013 and download all email back to beginning without problem AND QUICKLY, not throttled at 20-25 each fetch! Google says that Zoho is misconfigured, which may cause errors. Google says any delay or limit on downloading is purely done by Zoho, no Google. The Zoho rep did not have answers, my tickets since have been unresponded to. At present I have just 125K of my email up to Feb 18 download, none since. And this is for past two days.

Regarding Zoho, they suggest I change setting to fetch and delete, that by deleting email off of GMAIL, Zoho will then work. They also say that deleting will not actually delete from GMAIL. Google GMAIL says otherwise.

So, my problem. Zoho Mail is not working. Zoho has stated in tickets that apparently they know the problem exists, no fix anticipated, no further action. And no further action appears correct as two queries to the support ticket since then have gone completely unanswered. Now, this morning, I have spent over an hour and a half on chat with a rep about this, then she FINALLY says she is not in Mail group and cannot really help after all. Gave me 800 number to call, which only got me voice mail.

So, does anyone have suggestion or fix to fetching email that does not involve deleting messages from GMAIL? Or, is Zoho hopelessly broken and not interested or likely to address the matter?