If Cash App payment could not be sent from your account, you need to take the steps mentioned above and understand why you are having this issue.
If the card number you entered on the Cash App transfer page turns red then this happens because you may have written the wrong payment details of the recipient. You should re-confirm the payment details and try again for the Cash App transfer.
for more details: https://www.cashapphelps.net/blog/cash-app-wont-let-me-send-money/#:~:text=If%20the%20card%20number%20you,for%20the%20Cash%20App%20transfer.
Regards,