Wall charger a little burned at its tip, is it OK to use like that?

See in the picture linked below, this is a OnePlus 3T dash charge wall adapter.

https://drive.google.com/open?id=0B7tHPP...

I picked Samsung since I didn't find the right device here. But electrically speaking,

it got a little burn from the wall, because there was an issue in the hotel room I was staying in.

It IS working, however I am not sure if I should keep using it.

What do you think?