Unknown apple pay phone number won’t delete

When I was making a recent transaction on my phone using a credit card, the phone number associated with the card is one I have never seen before. This is not a number associated with me in anyway, it is not my cell phone number, nor my old work number. I have literally never seen this number before. When I checked in Settings, this strange number was listed first, with my name under it, and my actual phone number was listed below it. When I tried to delete the unknown number it keeps reappearing. What is going on here?