Something that sounds like “swift number” that’s used to refer to a doctor’s office number

I almost got lost getting to an appointment because I never heard this term before. I have a hard time understanding people on the phone and I understood “street number 370”. It was actually this “swift” number 317.

I’m a little hard of hearing on my native language as well, but it’s slightly worse with English, I’m so frustrated lol

I just want to know what the correct word was