I'm assuming you have the vinyl awing? If it is the cloth type then diss-regarde this answer.
I do not know how big a spot you have but I have had good luck with this product RV Awning Repair Tape
Awning Fabric Repair Kits on Sale
They list 2 types there. The one I had is the second one in the green package. It is sold at many RV type stores.
Duct tape I would shy away from. The weather will shred it in about a year.
I have had the RV Awning tape on living outside on the T310 now for 3 years and it still is on as good as the day I put it on. Make sure the awning is clean and dry before putting it on.
Good luck and hope this helps.
John
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Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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