GPS module and mount slide off of supplied stick.

I am almost finished with my project but unfortunately got stuck when it came to the GPS module (naza). When I went to place the module itself on the provided stick, it was not a tight fit and would slide up and down on the stick. That was also the same for the mount. If I use hot glue it solves the problem but is there a right way to make it secure? What am I missing? Thank you

 

Here is the photo.