Any help please? I've got these two pieces stuck together and not sure what to try! I don't want to break the pieces...
A possible solution I frequently use in such cases:
Cover the transparent bar into something soft, e.g. a few layers of paper tissue and fix that part in a vise or a pliers. Tissues will prevent the tool from leaving marks on the bar. When the bar is sufficiently fixed you can simultaneously pull and carefully rotate the yellow piece back and forth until it comes off. You can use some soap to make it easier.