Detect Duplicates button not showing in ribbon

Hi All

I have a Duplicated Detection rule on Campaign responses published - based on the exact match of subject.

The button does not display in the Campaign response area when (either myself or sales people) multiple records are selected. The button displays in Accounts and Contacts where I have similar rules published.

Any ideas what I am doing wrong.

I can schedule a job on the rule - but I want Sales people to run it on their responses when they get assigned them.

Cheers

Andrew