This sounds like the lateral side arms need to be adjusted. It is pretty much a part of the normal height adjustments procedure except you'd do it on one arm only. Unless you see the fabric rolling on and off the roller bar <strong>very</strong> unevenly, the level of the front bar would depend only on the adjustment of the side arm brackets (see SunSetter' illustration attached below).
This is a job that has to be done with a helper.
- Fully open the awning, then unplug the power cord.
- If you don't want to adjust the height in general, only the sagging side, you would only need to adjust that side's arm bracket.
- Clamp a bubble level to the front bar
- Have the helper lift the sagging end of the front bar a couple of inches higher than its level height.
- There are three Allen cap bolts (6mm Allen) on the side of the arm clamp. Loosen them 1/2 turn - do not remove them.
- There are two recessed set screws on the arm bracket. To raise the arm you need to loosen (counterclockwise) the screw closest to the square bar with a 6mm Allen wrench, then tighten (clockwise) the one that's furthest away from the square bar. Loosen first, tighten next. 1/2 turn in each direction.
- You don't have to go too far, so have the helper let go of the front bar after each 1/2 turn and check the level.
- Once the front bar is level, tighten the set screw closest to the square bar all the way in to secure it.
- Tighten the three Allen cap bolts on the side of the arm clamp.
The fabric is probably going to sag a bit so you may need to adjust the Open setting.
Cheers!