I had something similar happen a couple of years ago.
My thing is that I don't answer my phone if I don't know who 's calling. Yep, spammers, despite my number being on the do not call registry. A couple of years ago, some number would keep calling me at different hours and such. The voicemail that always followed was from the local school for the deaf, asking if (student's) parents were home. This continued for a month or so until they called very late at night once on a Saturday. Picked up, told the dumb bitch on the other end there was nobody here by that name, that they had the wrong number.
"But your number's in our database."
Fuckin' no, it ain't. Told them it was the wrong number, to stop calling me.
Few days later, guess what, kids? They call back. Same deal. "Wrong number", "don't call here again", blah blah. Dumb bitch said it won't happen again.
Later that week? They fucking text me about some group project asking if (student) would attend. Told them via text the same damn thing. It seems to have sunken in.
Saved the number as "Deaf Fucks" in case they try calling or texting again. Hasn't happened yet.