hold off on the water repellant
zip dee usually advises against applying anything to the cloth, except when cleaning.
often the acrylic fiber dries out so much that leaking is common....mine 25 year old curb side did the same thing.....
so try this first......open the awning completely and wet it down completely with a fine mist low pressure setting. really soak it good from the top and bottom.
wait 30 minutes and repeat.
if the awning is soiled at all now wash it with a wide soft brush, mild soap/water and repeat the wetting step. if it's not at all soiled just wet it for the 3rd time.
roll the awning back up while wet......that's right while wet.
wait 24 hours
open awning again and check for "rainproofness" with a water hose stream rolling gently over the surface. fibers should have had time to reexpand and recover their original function.
of course if you have small holes or big gaps in the fabric....it might be time for new cloth.
also i think zip dee now markets a product for awning coating?
check their web site.
cheers and let us know what happens