Every transaction that you make by using the app, you need to authenticate it using your PIN o,r touch ID. But if you’re facing an issue while authentication, then you must check the PIN that you’re entering or the finger that you’re putting on the scanner. If these steps don’t help you, then dial the Cash App phone numberto get assistance in order to get the issue resolved.https://www.mailsupportnumber.com/cash-app-customer-service-number.html