Create a rule using the asterix wildcard to filter attachment file name matching DHL_report_*.pdf:

1. Go to Policy > Policy List.
2. Click Add > Other.
3. Select Recipients and Senders. This rule will apply to incoming messages.
4. Choose Recipients and enter "your Domain: *@<your_domain>". Make sure that the Sender option is from "Anyone".
5. Click Next to go to "Step 2: Select Scanning Conditions".
6. Under the Attachment section, select Name or extension.
7. Choose Attachment name and type the file name with the asterix wildcard. For example, "DHL_report_*.pdf".
8. Click Save.

You will stop receiving any attached file with the same file name that you have blocked in emails.