The way Apple Wallet works is, you enter the card data and Apple encrypts the data and sends it to the bank. The bank has the key to decrypt the data and they match what was sent to their records. Some of the data is your name, address, DOB and other identifying information. If the information matches they send back a message saying they’ll contact you. The bank decides if it’ll be text, email or phone call. You will see a partial phone number or email. You cannot pick method of contact. Once you receive the code, you enter numbers and agree to terms and conditions and card is added to iPhone.
When you see the message to contact bank, it’s almost certainly either information doesn’t match or you’ve tried to enter the card too many times within an unspecified period of time. You must contact the bank and verify the information. In most cases it’s an inaccurate phone number or email. Banks may have the correct number, but the cell phone is not marked as primary number.
Many banks use a third party service to do the verification. The third party can have wrong information. Once the bank updates their system to could be several days before the third party syncs data from the bank.
Generally, the bank support team is not well versed on how Apple Pay works. If you can get through to a higher level of support or a specialist in Apple Pay, things can be updated quickly.
Lastly, your card may need to be reprovisioned in order to add it to Apple Pay. The bank or third party provider may need to perform the reprovisioning.
If you’ve questions, please let me know.