Have no idea who or what this is.A7

I am receiving multiple phone calls to my work number from 971-277-3732, which is apparently a collection agency. I attempted to call them back to let them know they are calling the wrong number and was cut off several times.

I keep getting calls on my work phone number for someone else. I've tried to answer the call, to tell them that the person is not at this number, but when I hit '1' to connect, it clicks a few times and then drops.