my ipad mini not conected to itunes and not activat it ifter restoring also the sim not shown up

suddenly my iPad mini not shows up the sim card and give searching all the time and also not connect to iTunes

then i made a reset for all sitting but after erase all data it give me message canoe activate your IPad i tried to connect with another cable

it not work also and not given any thing in the windows but when i used my cable in another device it work very well

before this 2 week i did one mistake i tried to charge the ipad with car charger in Bus the voltage was 20 VDC the adapter charger was damage

and i removed the iPad immediately and i charged normal from this time the 2 problem began to appear