Awning Stains

Looking for advice as how to clean stains on the underside of my awning.Should have dried it off before rolling it up,but We were in a hurry.Have tried Camco liquid cleaner and several household liquid cleaners without much success.The awning is almost new and I hesitate to use anything abrasive like steel wool.Would appreciate any input on this.Thank You. Will.
Awning Stains

Just went thru same thing (top and Bottom). Sprayed with water/bleach solution, vary weak bleach. Rolled up and let set for few minutes, then opened, washed down with automatic dishwasher solution, both sides look like new. Some stains are actually a mold, and soaps dont kill them first.