@Shakunt 

Hi, thank you for posting on TP-Link Community.

Do you mean you are unable to login the router web interface with correct username and password?

For the router login password, please note that it is not wireless password, if you don't have any other possible password, please try "admin" in lower case for both username and password. However, if admin doesn't work either, please reset your TP-Link device to default settings by pressing and holding the reset button for 10s.

Please note that all the configurations will be cleared after the factory reset, you will need to set up the router again.