Turnitin flags potential instances of source misuse in a paper by highlighting them. This highlighting can have the effect of lumping all source-use errors into a single category. Since using sources well requires a constellation of skills working in tandem, identifying the specific ways you may have misused sources is the first step in revising your paper.
The pages linked below describe kinds of source misuse you might encounter in a Turnitin report. They are intended to help you identify each type of source misuse and to know the most effective way to address it.