You have configured an IBAN detection policy
You notice that incidents are generated as expected if you select 'check for existence' in the polilcy, but if you change this to 'Count all unique matches' the policy no longer triggers incidents.
Release : DLP 15.7.x
Upgrading to 15.8 or later will resolve this issue
Workaround
Do the following on Enforce and all Detection servers:
1. Open the file "...\Protect\plugins\contentextraction\DLPCustomPlugin\manifest.xml"
2. Set disabled="true" on the following line:
<plugin id="DLPCustomPlugin" version="1.0" spiVersion="1" disabled="false">
3. Save and close manifest.xml
4. Restart DLP services.