I don't know if it's ok to say this sentence, and if not what I should say instead. Does it sound redundant ?
The phrase "by any chance" fits well at the end of the OP's sentence You can also use it in the middle of the sentence.
Do you have any advice? is also correct, but the use of the "by any chance" makes a polite or less direct question or request.
It's not redundant, although the word order rubs me the wrong way - I'd rewrite the sentence as:
Do you, by any chance, have any advice?
It asks for advice, politely emphasizing that it's perfectly okay if they don't have any.