URL shown as black-listed, even though it is not listed in the black-list

This is now the second time that I've come across this issue.  A URL gets classified under "Black-List", but it is not listed under the black-list.  The only way to permit access to the URL is to completely unblock it.

We're running Web Security 7.6.0.

Is there another hidden black list somewhere that I'm not seeing?  Or is this a bug somewhere that, even though a URL is removed from the custom black list, Websense still thinks it's in there?

Any assistance or information would be appreciated.

Thanks.