@yellowmatic You could try Smart Switch. if you are still on UI 6.11 it suggests yout Tablet is being used outside of the intended region,is the device from a reliable sources , need to be careful with some sites. CSC (country specific code) can be viewed via About Phone-Software Information-Service Provider Software version . Check the 3 letters.
I do not work for Samsung or make Samsung Products but provide independent advice and valuable contributions.
