Denial & Appeals: How to Win Appeal Section 1253a

I had been laid off from my job on 11/9/17 due to hospital closure. I did not file for unemployment right away because prior to the hospital closure I had been applying for jobs and had had a few interviews. I had thought I would get a job offer prior to my official date of lay-off. I ended up deciding at the beginning of December I need to file for unemployment. I have been approved for unemployment benefits from the date I applied till now. I am trying to get back pay starting from the date I was laid off. I had a phone interview regarding my application for back pay. However the phone interview was very minimal. The only questions that was asked was what date do I want to start being payed for and why I didn't apply for unemployment when I was first laid off. I was then informed that I would need to fill out paper work that will be sent to me via mail to be eligible for the back pay. Instead I received a letter stating "YOU ARE NOT ELIGIBLE TO RECEIVE BENEFITS UNDER CALIFORNIA UNEMPLOYMENT INSURANCE CODE SECTION 1253A." I would like to write a letter of appeal but I am not sure how to go about writing a successful letter that will help me win my appeal.

Please Help!!!

Denial & Appeals: How to Win Appeal Section 1253a