The ticket rules have an order of execution from Top to Bottom. This is very important to remember because the next time you are scratching your head wondering why one of your ticket rules are not working it is most likely because a previous and later ticket rule is interfering with it.
The main thing you want to look out for is later ticket rules down the chain are not changing or affecting any other rules along the way. This can happen very easily and usually often so keep that in mind. One of the simplest troubleshooting tips you can do is to disable ticket rules one by one after or before your ticket rule that is not working until it starts working. Then you will know who the culprit is.