never+don't is correct grammatically ??
never don't stop / never don't give up

is this sentence correct grammatically??

i think that double negation is not grammatical.

Question

never+don't is correct grammatically ??
never don't stop  / never don't give up

is this sentence correct grammatically??

i think that double negation is not grammatical.

Answer

No, is't not.  As you well said before, you can't double negate in English.

"Don't stop, never give up"... I think that there is a song called 
"Don't stop, never give up" by S Club 7. Hhahaha.

I hope it helps.

Answer

No, never and don't don't go together! ;^)
Some double negatives are OK - but not these ones.