Get "Activation Required" message when trying to log-in to Zoho Android App

I had been using the Zoho Mobile App for a couple of weeks on my Android phone, when suddenly today I got this:

"Sorry but you do not have permission to access the Zoho CRM Android Application. Please contact your Zoho CRM account administrator for any clarifications."

Here's the thing, I am the administrator and the app was working fine last week. I haven't changed any of my own settings, and there is no option (none that I can see anyway) for activating mobile access in Subscription Management, I assume because I'm the administrator and only person on this account. I can log-in via my laptop just fine with the same username(or email) and password.

Was this a trial version of the app? I'm just getting started, so I'm not syncing any email or calendars. I'm just using the app as a convenient pass through from my phone so that I can get to my leads/accounts/potentials data.

Any assistance is greatly appreciated.

Thanks.