Got a denial letter for unemployment, what now? - what worked for you?

I got a denial letter last week saying I left my job voluntarily, but I was let go as a dental hygienist. Any experience at all would help. My employer's version of events does not match mine, and I have emails that show it.

File the appeal before the deadline, even if you are unsure. You can gather documents afterwards. That is the one part I would not wait on.

I printed my emails in order and wrote a one-page timeline. The hearing officer kept going back to it.