Having issues with my 2016 Tahoe LTZ I purchased last November. The fob will no longer open the liftgate. The lights will flash, but the liftgate will not open. Get in truck and push button for liftgate and it will not open. Turn switch to off then back on a few times and press button, liftgate opens. Liftgate will open properly from then on until I shut the truck off again. Now, when I lock the truck with the fob, it no longer beeps when it locks. The remote start will not work. If I try to remote start with the app on my phone, it says to check if the fob is in the vehicle, which it isn't. Dealer has no clue. Anyone else had problems like this? Thanks. Brad