My BSNL SIM Showing Error 40, DF a8h & 50, What to do

How can i resolve the error 50, 40 or DF a8h in my mobile screen connected with BSNL SIM card, what are these error types, why this occur, and Is there any problem to my smartphone with these errors,...

source https://bsnlteleservices.com/bsnl-sim-error/