Door openers that attach to doors pull on the upper middle of the top section causing the center of the section to bow over time.
Garage door bows when opening.
You might have absentmindedly unplugged the operator as you were exiting the garage through your internal door to the house.
In some cases basic exposure to the elements along with temperature fluctuations may result in bowing.
I believe there will always be a slight bowing as the pushing and pulling of the door exerts pressure on the rail.
My gdo rail bows slightly when opening and closing as well.
There are several factors that may cause a garage door to bow in the center.
Sometimes a garage door won t open or close for one reason only the operator has no power connection.
In the funniest of scenarios the problem will simply be due to an unplugged power cord.
In other cases the weight of the garage door in conjunction with an automatic garage door that is attached to the center of the door may be the cause of bowing.
My only suggestion is the ensure that the door operates properly and easily without the gdo and then re connect the door.