Step 1:
There are two possible reasons: First, PATCHBOX Plus+ Cassettes must not be used in a 365 Frame, as the Cassettes are too long and too heavy for the Frame without Mounting Rails.
Step 2:
If this is not the case, you probably have not used the provided Mounting Rails for your PATCHBOX Plus+ Frame or one side is not correctly mounted with the Mounting Rails. To find out how to mount the Mounting Rails, click here.