spam filter not filtering on sender

Hello:

I have an issue with the spam filter. I wish emails sent from a specific email address to be dropped.

I have two rules in my filter.

1. where "sender is" then multiple addresses
2. where "subject contains" with multiple listings.

I have an issue where the notification that a job has been closed is being sent to a CC recipient with an incorrectly spelt email address. The postmaster (the address I've listed in step 1 above) responds that the recipient can't be found. This reopens the request.

I have also added the word: 'undeliverable' into the second rule (as this is placed in the subject by the postmaster sender.

I have updated these changes - SDP responds that it has updated the rules successfully. But the 'undeliverable' responses continue to re-open the request.

Any help gratefully received.

Alistair