The spring may have broken or the rivets that hold the spring to the tube may have sheared. In either case if you do not feel resistance of the spring while opening the awning there is no safety issue now.
With the spring gone tie BOTH ends up until you get home.
If it is an A&E they use only one spring and most likely at the right hand end. You will see 4 rivets that hold the end cap to the awing tube and a shear bolt that holds the awing axle shaft to the arm. If the shear bolt is not sheared off and there is no tension on the awing the spring has most likely broken. Extend the awing, support it with a ladder, remove the shear bolt, remove the arm from the shaft. Now drill out the 4 rivets that hold the cap to the tube. You can now slide the spring out of the tube.
When replacing the spring. remove the end of the arm that attaches to the trailer. Rerivet the cap, replace the bolt that holds the arm to the shaft. Follow A&E instructions for the number of turns to preload the spring and secure the arm to the trailer. Once you start to prelaod the spring do not let go of the arm as it will come back and hit you.
WBCCI 12156 AIR 3144 WACHUNG TAC NJ6
2004 Excursion 4x4
1991 34 ft. Excella +220,000 miles, new laminated flooring, new upholstery, new 3200 lbs axles