Your account's top up feature may not have been activated yet. This means either:
A) You have not completed verification yet; or
B) You have not registered your bank account yet; or
C) You have not linked your Xfers account to one of our Digital Goods merchants.
Check your account dashboard to see if there are any warning messages informing you of your account status, or you can contact our Customer Support Team, by filling up the support form.