How can i win my unemployment appeal?

I was suppose to do overtime starting 4 hours before my scheduled shift but didn't come in to work until my regular shift. The HR manager told me it was a write up as usual, clocked in,worked 45 minutes and then was told I was terminated. Before clocking out she changed her mind and said I was suspended, then she called two days later saying I was fired again. The company is appealing my unemployment stating I was given a tardy and that was my final tardy. In the company handbook it states when u don't do overtime it is a write up and you have to refuse 3 times before terminated and that was my 1st. How can I win?