@Keep-Learning1 First , are you able to add your new card on Self Serve My Account to replace the old one?
If you can, then try using Incognito mode , or another browser like Edge/Chrome/Firefox , to login to My Account and make a manual payment. Click the button Reactivate my plan. It will bring you to payment page. First try to pay by Amount Due. If it works, good. In case the payment fails, try once more time but time time, use the option "custom amount" option and manually enter the plan amount.
Once payment is made, logoff from My Account and restart your phone once
