Panel Separation
Panel separation is caused by one side of the cover stalling while the cover is pulled into the extended position. If you attempt to pull the cover closed with one side stalled, the panels can come apart.
Reassemble the Panels
In order to put your panels back together you must remove them from the rails.
If your cover uses gas springs, you will want to view the following video:
If your cover does not have gas springs, you will want to view this video:
Put the cover assembly upside down on a surface that will protect the finish and allow you to work on it. To put the panels back together, you'll need to reconnect one side and then pry the opposite side back in. After doing this, you will need to measure the hinge gap and tighten as required.
Confirm Proper Alignment
At this point, you take a look at your cover to see what caused the panel separation.
If your cover has gas springs, you will want to view: https://peragon.zendesk.com/hc/en-us/articles/360046971974-What-to-do-About-Rough-Operation
If your cover does not have gas springs, please view:
Ford owners: https://support.peragon.com/hc/en-us/articles/37205050731923-Rough-Operation-for-HDx-models-using-BoxLink-System
GMC/Chevrolet/Ram Owners: https://support.peragon.com/hc/en-us/articles/27379129442579-Limited-HDx-Fine-Tune-Ramp-Adjustment-for-GM-RAM
Toyota Owners: https://support.peragon.com/hc/en-us/articles/23084304388115-Rough-Operation-Limited-HDx-Direct-Mount