touchscreen not working due to ios update and overheating

hello. i have a ipad mini from 2015. there was an ios update and clicked on it to install. after that the ipad got hotter and hotter, to the extreme and a black screen appeared with the notice that the ipad is overheating. i could not switch it off or do anything, put in on the table and after a couple of minutes it had cooled down. but since then, the touchscreen is not working anymore. i did a hard reset and eventually connected it to my pc for a factory reset. now the ipad is asking for the country, but still tocuh is not working. has anyone else encountered this problem and has a solution? due to the extreme heat, can the touch be damaged? but starting a ios update can't cause the ipad to overheat?! the ipad is six years old, but was still working well :-(