Brighthouse Networks ongoing phone problem Livonia, Michigan

For about the last two months, I've been experiencing a recurring home phone problem.  For one number, and one number only, caller ID displays the phone number with the area code.  Then the area code is dropped and then returns.  It could be there for several days, then gone again, and return.  Brighthouse has atempted to fix this problem without success.  Originally, about two months ago, they sent two techs, who didn't have any success.  

They went back to the office believing there might be somehing on their system causing the problem.  Again, no success.  Each time, 'someone" would get back to me.   Never happened. 

I've recontacted them at least three times re the status as the problem was still there.  About two weeks ago, they sent another tech.  He never saw this problem before but would take to other techs at their facility.  The problem persists.  As requested I got out he phone users manual, checked what they asked me to check, and made sure settings were as requested.  The phone number involved just happens to be my ICE contact.  If I call that number from caller ID when the area code isn't displayed I get someone else. 

I wasted at least 45 minutes with an agent via 'chat' attempting to get the name of the person in charge of the local office.  No luck there either!!