Denied unemployment, how do I appeal? after 8 years as a procurement assistant

My claim was denied after 3 weeks of waiting, and the letter says I have a short window to appeal. I do not usually post, so bear with me. My employer's version of events does not match mine, and I have emails that show it. If you have appealed before, what helped you prepare?

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.

Thanks for writing this out. I went through something close to it 10 months ago, and it settled down once I kept a simple log of every call and form.