I really need help. I have nits and got treated twice. I use repellent everyday so I don’t know...

Nits are head lice.

You should buy a head lice treatment kit at the drug store. It usually consists of two medicated shampoo treatments. Under no circumstances share combs and brushes and headwear.

Then you have house cleaning to do:
Bedding, combs and brushes, head bands, hats, furniture, etc.