What do I say about why I left my last job? - any advice?

I have an interview next week and I am unsure how to explain why I left my last job as an insurance claims processor. I do not want to blame the company. Do they ask follow-ups?

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.

If a company has been in the news for layoffs, you can mention that. Often the interviewer already knows.