Actually the main issue was happening due to not set the DNS settings properly. I reset the DNS settings first, then reinstalled the game. After doing this methods perfectly, the problem got solved. Now I am not getting any such kind of error while playing the game. I must say this article https://www.thewindowsclub.com/fix-the-roblox-error-code-403 helped a lot to identify the issue and resolved it.
M
MoriahPrice
@MoriahPrice