Visit nearby Service center to get resolve this issue.

But one suggestion from my end is, get support from Samsung for doing any changes in the SW. Otherwise, if you face any other issues with the phone in future (After installing apk), it would be treated as Out Of Warranty.Just a suggestion 

Plz make sure that the TV which you are connecting should be compatible with S8 & also TV needs to be updated with Latest SW. Then only it works.

Plz make sure that the TV which you are connecting should be compatible with S8 & also TV needs to be updated with Latest SW. Then only it works.

If it is specific issue with Reliance Jio SIM, then need to check with Reliance store.If issues with any other operators, then should be problem with Message centre number