Don't even tell them to remove your phone #. Cause they'll request your number to delete it...but what they really do is
get you phone number and use it to charge their bills to your number. Just simply don't answer when you see their phone number. Reject it on your cell phone and delete it. On your landline, just pick up the receiver and hang up immediately.
They start out like "can you hear me, sorry about that, I had a problem with my headset" then proceed into sales pitch about a resort. And a few simple questions. Other sites say this is a scam, and they are obtaining your number to charge your account.