Try hard reset, by pressing volume down and power key..then choose the option to clear cache file...It might solve the problem...now a days various problems are there in samsung devices...
Please perform the below mentioned steps to resolve the issue:
To Reset S Pen - Insert the S Pen into the slot. Then, open the S Pen remote setting screen and tap More → Reset S Pen.
For further assistance, register your concern in Samsung Members Application (Open Samsung Members Application > Get help > Send Feedback > Error report/Ask questions).
