Replace Your PayPal Account in Google Wallet Before It Gets Deleted
PayPal support is ending on June 13.

If you have your PayPal account linked to your Google Wallet for purchases, you need to update your payment method ASAP. Google is ending its support for PayPal integration, and users in the U.S. will see their PayPal accounts and transaction histories deleted from their digital wallets on June 13.
That means that Google Wallet users will need to replace PayPal with an alternative payment method. If you have recurring payments, such as subscriptions, set up with a linked PayPal account, you'll also need to go to the individual merchant site to manually update your payment information.
Connecting PayPal to Google Wallet allowed users to maintain and manage their cards and bank accounts centrally in PayPal rather than separately in their digital wallets. Google had already stopped new PayPal links as of April 11, though users were still able to pay via previously connected PayPal accounts from their Google Wallet.
Note that Google Wallet will support PayPal-branded debit cards, and full PayPal integration will still be available for Google Wallet users in Germany.
How to update your payment method in Google Wallet
To continue using Google Wallet after the PayPal integration ends, you need to have at least one credit or debit card added to your Google account.
To add a card, open the Google Wallet app and tap Add to Wallet at the bottom of the screen. Tap Payment card > New credit or debit card and either add the card information manually or use your camera to do so automatically. Tap Save and continue > Accept after reading the issuer terms and conditions. You may need to verify the payment method—via email, text, bank app, or temporary deposit, for example—to complete the link.
Alternatively, you can add cards from your bank's app or website if "Add to GPay" is supported.