Don't know that it's the same awning, but on ours there is a black knob on each of the support arms. Just loosen the knob, let the awning down to where you want it and tighten the knob. Be sure to remember to loosen it and return to the original position before putting the awning back in. Assuming you're talking electric awning rather than manual.
Trailerless but still have the spirit
2013 Rockwood Ultra Lite 2604 - new family
2007 Rockwood ROO HTT - new family
2003 Ford F-150
4 doggies - We support Adopt/Rescue.
Sam, you were the best!
Cubbie, Foxy, Biscuit and Lily - all rescues!