mobile phone number on the dark web

I was informed by my credit monitoring company that my mobile number is on the dark web. They told me not to be too concerned since I haven't been a subject of identity theft. Anyway, since then I am barraged with spam messages. The credit monitoring company provided me with a person's name, email, and physical address of who is assuming my phone number. Anything I can do to prevent this from continuing short of changing my phone number, which I've had for over 20 years?