Day time training and Night Time Training are not the same.
The bladder is slow to mature. Most cases a child's bladder can not hold it overnight. And the signal to pee is just not strong enough to wake a child up.
Rewarding can actually make it worse, it can add a level of stress which stress/anxiety can cause bed wetting.
She can help clean herself up, this is NOT for punishment but a way for the mind to train itself.
Having her lay down for about 30 minutes then getting up to pee can help.
Also waking a child up in the middle of the night is not affective because it will disrupt their natural sleep pattern. Plus most of the time the are not fully wake enough to empty their bladder.
Just let it go. She'll stop when her body is ready. If it goes past the age of 6 for girls, then the doctor may suggest other treatments. However if there is a family history, than they will factor that in.
My 8 year old son wets the bed. I did the same thing and it continued till I was pretty old. His doctor isn't worried because there is a strong family history of it. We've given it till the age of 10 and then see what else we can do.