No service or Searching in iphone 7 plus Model A1784

I had no searching and some times No Service in my iphone 7 plus after the lasted update from IOS. Couple of weeks ago, the problem happen in a contentious basis, i tried every possible solution, but it did-not work.  The Sim Card work fine in other phones and other sim cards doesn't work in my iPhone. I contacted apple support, the guy asked me to reinstall the ios, then i stuck with the activation. It keep saying that the iphone could not be activated , and some other time it says the iphone needs an update. i went to Genius bar, they told me that is a hardware problem and i have to pay charge 1400 AED to replace to same set and with only 3 month warranty. Honestly i was shocked by this policy. This problem started to show up after the latest  update and apparently i am not the only one having this problem as i found thousands of people have the same issue, even apple issued a repair statement for some models form Iphone 7. Apple is keep forcing us to buy new phones by keep making updates that doest suite our old iPhones.