No link between smart meter and display

I have two meters.both changed to smart meters on the same day. One works perfectly and one will not connect to the display. Logged the fault twice. Phone always busy. Sent emails with no reply.
The guy who fitted it knew it didn’t work and just said bulb would fix it in a couple of days. I should have locked him in till it worked!!!so…what to do now? Maybe if I put lead round the meter they will get no readouts and might do something. Come on bulb, when I first joined you a couple of years ago you were so good. I think you may have got too big!