All of our bikes have been inspected and tested by QA Mechanics at our warehouse to ensure that the battery will fit and sit properly. Below is a link to detailed instructions about installing the battery pack.
If your pack doesn't seem to stay in place, here we detail the locking mechanism a bit more
This is an example of how the clicking noise is just the pin retracting to allow the battery to go in, but it doesn't mean its locked
This is an example of how a bit of extra pressure on the top will keep this seemingly loose pack on its place after the pin locks into position.
We also recommend inspecting all your battery dock items on the frame are secure and tight because vibration can and will loosen up screws with time.
If your battery pack is securely locked but it still moves, please record a quick video and contact our support team for detailed instructions on how to do an inspection.