Appeal deadline questions after an unemployment denial - 26 weeks in

My claim was denied after 26 weeks of waiting, and the letter says I have a short window to appeal. 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?

Legal aid offices and some workforce centres help with unemployment hearings at no cost. A call is worth it.

Thanks for writing this out. I went through something close to it last year, and it got easier once I kept a simple log of every call and form.