In bullet it is fairly common to play until the end of the game, even if the position is obviously lost and the opponent has a significant time advantage.
Never give up in bullet in the middlegame or in the endgame if you still have some valuable pieces. This mistake was made recently against me.
I won't advocate for playing queen vs king, that's ridiculous if the opponent has more than, say, 4/5 seconds.
However, if you are completely lost, a good idea will be to complicate the position even if you are not playing accurately, since the losing party has an interest in complicating the position in order to see if it can muddy the waters, hoping to increase the odds of a blunder from the other side.
I am going to show an example of resigning too soon.
Watch this game:
https://lichess.org/N2LghL2porQV
I thought I was winning, but black has rxe1! qxe1 nf3! and white is completely lost. But he didn't find this and gave up. I was completely surprised when checking the game afterwards. If you have a good amount of pieces, even if you are down in material, you ought to continue and you might turn the tables.
By move 17 I could have easily won by nf6! but two moves later I was lost. This shows that one shouldn't surrender so early. My opponent, had he continued, might have played rxe1, which is a move that one could easily do when out of ideas, and then he could have found nf3!, after which I would have been completely lost.
All of this is to say, surrender only in completely lost positions with no hope, and not in positions where you might swindle your opponent. Practice will help you with distinguishing them. Obviously that my advice applies in bullet and blitz(with no increment), but certainly not in rapid and controls where you have much more time.
