Sure, you can! If you will make it, you will need following the steps below:
- Do a new payment using the email account.
- After the payment, for security reasons, please, send us your app ID and email address, we will associate it to your payment.
- We will request the partial refund about the current payment.
If you need any help, feel free to contact us :)
We recommend that you pay before canceling in Paypal, so your app does not go back to the free plan.