Transport rule with Regular Expressions

Hi, I've tried setting up a transport rule

New-TransportRule -Name "Some Name" -SentTo 'something@something' -RecipientAddressMatchesPatterns '\S\*\d\d' -RejectMessageEnhancedStatusCode

"5.7.1" -RejectMessageReasonText 'Some Reason"

I'm using Regular Expressions to achieve match for any address containing letters and any number between 00-99 (ie. cobalt65@somerthing) but it doesn't seem to do the trick as no messages qualify.

I thought the less is more rule applied, if the rule is too loose it would get more false positives, but seems not a single message was affected.

Any ideas?