There are several reasons why the Paper Money deposit option may not appear on your Cash App.
You could be in an unsupported area. At the moment, the Paper Money option is only accessible in the United States, Canada, the United Kingdom, and Ireland. If you are not in one of these regions, you will be unable to use the Paper Money option.
It is possible that your account has not been validated. Certain services, notably the Paper Money option, need Cash App users to validate their accounts before they may use them. You must submit your name, date of birth, and Social Security number to validate your account.
Source:
themoneyflow.net/how-to-add-paper-money-to-cash-app