First unemployment deposit is late, what should I check? (update)

I was laid off as an event coordinator and filed right away, and I have been certifying every week. I called the state line four times and only reached a recording. What would you check first?

When I finally got through, the agent said my employer had responded late. Once that cleared, back pay came in one payment.

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