Can't purchase ZP via PayPal

I'm having similar issue where it's saying I cannot purchase ZP I have to be atleast level 6 in Crossfire even though I used PayPal yesterday to buy ZP and I'm a SFC rank 5...

Make sure you have enough funds in your Paypal account ( Although I'm sure this is not the issue)
Refresh the page.
Try using different web browser.
Reset computer.

This is as far as my knowledge can help. Hope you can fix your problem.

Did you changed from global to your country when you enter deposit page before you choose paypal ?