If your Cash App account doesn't have sufficient funds to pay, then you may face the issue of transfer failed while adding money to Cash App. But occasionally, because of some technical errors, it is possible to encounter these errors. If you can't add money to Cash App, it can be due to the following reasons.
1: if your internet or wifi connection is not working.
2: Have not updated the Cash App on your and still using an older version of this application.
3: If you have not activated your Cash Card, you might not have the ability to put in money.