Chosen Solution
I removed the rear case of my HTC one m8 and replaced the charging board as it was damaged. After reassembly the phone works perfectly with the exception of the sim card not being recognized. I have tried inserting it many times as well as putting tape on the card to make it thicker. Nothing has worked. Please help quickly! Thanks
I’m quite surprised to how you managed to make the sim card slot not working properly. Anyway open up the phone again. You may have loosened a cable at the top right of the phone. It’s a clip that connects to the sim card slot. Lift up the clip and get the cable out, then plug it back into the clip connector. Try the sim card again and see if it works.
