Likely, there is a dataset on data.gov published by CFPB which consolidates consumer complaints in a federal database.

https://catalog.data.gov/dataset/consumer-complaint-database...

BofA ranks first by the total number of cases which is to be expected given their footprint. What's notable is that BofA has actually improved over time.

https://github.com/axibase/atsd-use-cases/blob/master/Consum...