Enable Incoming: "Operation permitted for paid user(s) only."

Enable Incoming: "Operation permitted for paid user(s) only."

Hi,
One of our user had accidentally disabled the "incoming enabled", then we can't get it enabled again.   when clicking on grey icon checkbox "Incoming disabled" for following email accounts.

"Operation permitted for paid user(s) only."

Could you please have a look to enable this account?
marcos at potencia.net.br

Thanks.