Got a denial letter for unemployment, what now? (update)

My claim was denied after 21 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.

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

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