I notice some users give the Gamma Ball Hopper bad marks due to the hopper handles falling out. Admittedly they are not always perfect but here is a suggestion I gave to someone asking about this.
Regarding your handle problem: Sometimes the handles need to be put under tension to stay on properly so I usually just remove the handles and pull the opens end that insert into the hopper across each other well past the normal position. Imagine a wish bone and pulling in the opposite direction you would normally take to separate it. This creates a spring-like tension to keep the handles in place once you re-insert them into the hopper mounting bracket.
Disclosure: I have used Gamma hoppers since they became Gamma, I think they were just called Ball Hopper brand before that. and they are the best option. That said, when made in USA the quality was superb. I still have two made 30 years ago that work with some TLC. I have no financial interest in Gamma products but use many of them including string and other tennis products.
