New paid user: not receiving email from Gmail more recently than 2011?

New paid user: not receiving email from Gmail more recently than 2011?

I'm a subscriber to Professional edition+mobile+Zoho Mail. Activated Zoho mail three days ago. Since then I've been getting regular iphone notifications that new messages have arrived, but they are all two years or more old. It is as if the app is only syncing half a dozen messages an hour or something.
When I check Zoho email in a browser, no new email is showing up, but i appear to have all my email prior to December, 2011.
Sending email is fine. I've double-checked all the POP settings and they seem ok.
What is going on please?