Hey @Greg
What @Gaoler and @o99 said is correct. Really its an issue that starling gives us their transaction data in a different way to other banks. So their reference goes into a different field to other banks. We have an update to the smart rules which will allow you to put a filter on that field instead and should solve your problem. Sorry for the delay, it will be out soon!
I am finding it annoying too because i use starling for most of my banking! If you are looking for some specific payments you can see if you can make it work with the advanced filters alone in the mean time.