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I am sorry to know that you're unable to add a bank. You may try to add the bank manually instead of clicking on the Bank. At the bottom of the page, you should see the option I have a different bank (or sentence to add a bank manually). Then you can manually enter your bank details. Otherwise, you will have to try to clear cache and cookies, use a different browser or device, or try again later. If the issue still persists, please reach out to our contact customer service by clicking contact at the bottom of the PayPal website to see the contact options for help.