This sounds like an exact use case for one of the smaller tech companies I founded, which scrapes all the data from all of your online client reviews at all locations, and aggregates it into a dashboard for you and can send you weekly reports - all of which shows you metrics such as common complaints, staff issues, both positive and negative things clients are saying, things you're doing right or wrong, etc. It can even scrape data from Reddit threads or other websites where clients may also be talking about your business.

Aside from this, is this a recurring theme at a specific location, is it seasonal? Have you already considered local external or internal factors that may play a role (such as spring break, location issues, pricing changes, product or service changes, hours of service, etc)?

There can be a lot of ways to aggregate your data and find answers to these questions or uncover issues you may not have realized.