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That will require that (at very least) the Samsung device be disassembled by a skilled repair tech, and the ribbon cable to the touchscreen be re-seated.
Or perhaps the screen might need to be replaced altogether - it depends upon the extent of the damage from being dropped.
(How old is the S6 in question?)
(Where are you located? I would recommend your taking it to the nearest Samsung repair shop, and if I know your local zip code or town/city and state, I could recommend and list for you, all local Samsung repair shops qualified to do this sort of repair.)