However, if you think you have your previous Cash App login credentials with you, then it is definitely possible that you can access your account. For this, you can open the official website of Cash App or its mobile app on your smartphone. The main page is where you have to feed your login credentials. Here, you can just enter the new phone number or email address that you are planning to use with Cash App. Now, you can fill up the sign-up form with the correct, valid, and updated details.