Many people wrongly assume that card acquiring (or card acceptance) is something that is available to you, as a matter of fact.
It is not.
Card acquiring is something you have to 'qualify' for. Just like a credit card application looks at your credit and good standing, the same is applicable for card acquiring.
As a business, your creditworthiness and good standing have to qualify for a bank to be able to underwrite you for card processing.
See the attached video which explains it from a perspective of a money transfer business. Shameless plug.
https://www.youtube.com/watch?v=...