You can change your payment method at any time.
To do that, click on the shop icon or the cash balance icon in the top right corner. Then, click on the deposit amount you would like to add.
You can change your method of deposit at any time by tapping on the edit icon, which can be found next to your most recently chosen payment method.
Choose the payment method you wish to check out with (either PayPal, ApplePay, or credit/debit card), enter your details, and complete the purchase.
However, please note when changing your payment method, any withdrawals requested will not be affected and will still go back to the original payment method that your purchases were made with.