DLP policy matches report

Hello Guys,

We recently set up 3 DLP policies in test mode with 1 rule each . However we observed as below

1. The number of matches changes each time we refresh the report . Also the number vary a lot , sometimes it increases by 200 and sometimes decreases too. What could be the cause for same

2. The report shows a particular file matching multiple rules in the report . As per my understanding in case of multiple matches a file will match to only one rule/policy based on priority set

3. When i filter DLP policy matches report by a specific rule/ policy i still see rules appearing other than i have filtered.

Have you guys also observed the same and what is the logic behind the same