Consider maybe getting a call blocking device or phone.. You can google them and many are around $40.00 or so.If its a cell phone, some already have call blocking, if not, there are free apps on the web that will work for some. You can google this. If you have a smart phone, there is a free app called call control. Iphones appear to have apps also. Another one is called Mr. Number.

Your posts are correct, and informative, but you may want to consider 'maybe', removing 'maybe', as the word is superfluous.

....first world problems....

This number called my house phone at 5:10 AM. I AM SO MAD. Nothing like having a disabled person that takes 20 minutes to get out of bed normally to jump out of it to run to the phone thinking it's an emergency call.

I told this person to stop calling our LAW FIRM.  Hopefully, they will comply or face phone calls from US!  The person had a foreign accent.  When I called back, their mailbox was full and no message could be left.