Switching your account to a different community is not possible. But you can create another account in a different community.
Explanation: Since communities are distinct groups of PayCoupons users and also differ in other ways (such as the currency unit used), switching communities would be too confusing. Users in your old community would see your profile vanish from the directory. And since currency units change in relative value all the time, the value of converted coupons would have to change as well, or otherwise coupons holders would complain about inflationary losses.