[HELP] I restored my router settings to default

First of all let me admit I'm a complete noob haha lol, I should know this kind of stuff.

Anyways the problem is I restored my routers' settings to default ( management > settings > restore to default) and and one of the lights on my router turned red! now I know I need to put in my username and pass somewhere to get it running again, but I think I've forgotten where that place is lol.

Can somebody help a brother out? I'll appreciate it, thanks.

Which ptcl router u hav?

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