ahh..I see. Hope you get your oath date soon. Will let you know when my mom get hers. Looks like Cleveland hosts oath ceremonies at least twice a month :
https://www.ohnd.uscourts.gov/naturalization-schedule
I don't see any dates where they skipped...in fact they added additional/special ceremonies for June and July. Since it has been more than 30 days, I think it's worth for you to give USCIS a call.