I Have A Problem In My Business Analytics Course Asking To Find At Least 100 Err

I have a problem in my business analytics course, asking to find at least 100 errors in a data set of fictitious hospital data, such as customer id, address, name, zip code. Also, included is a attachment containing more zip codes and data that is linked to the hospital data. I have used sort and filter to find about 10 errors, but what is the best way to approach this?