I always seem to get them during dinner. I have registered to the do not call registry and that didn't work, and blocking the call helps sometimes. They are getting sneaky and using the same area code and even the local three digits to call. Sometimes they tell you to hit 2 to not receive anymore calls and that is a waste of time because they keep calling.
I think it's hopeless!
We don't answer phones unless we recognize the caller. If it's important, they'll leave a message.