Any hope to reopen unemployment insurace claim after accepting a job that falls flat?

I was on unemployment. I found a sales job and started working last week. The employer gave me a base salary and verbally promised an average monthly commission. In four whole days, I sold nothing at all so I told my new boss that I didn't think I was the right person to do the job. I'm a pretty shy person and just don't see a career in this position. Now, the boss asked me to work for at least a month just to cover other staff and I agreed. She also asked me to email her a resignation so her HR can know the reason why I will be leaving.

Can I still reopen my unemployment insurance claim after I leave this job even though I was promised an average monthly commission verbally while in reality there is no business, i.e., no commission? Or will I be disqualified for UI since I decline work?