I do not remember the Admin password for the Dlink DIr-882 router, what should i do?

All you can do is reset the router and reconfigure it. In order to reset the router press and hold the reset button on the router for 30 seconds.

In such condition you need to reset your router and configure it again

In this case you can try resetting the router and then login with the default credentials. User name is admin and the password should be left blank.

you need to reset the router and try with the default login information

You can try default admin password which is "blank"(which means you have to leave the password field empty) and then hit login.

if thats not working then in that case, you need to reset your Dlink router and for that, you need to press and hold the reset button for at least 30 seconds and then release it and then reconfigure it again.