Don't know how long you have had the trailer but whether just bought or bought new you need to go over things with a fine tooth comb. The screws securing the awning should be sealed up and tight...and checked every now and again. Same for the ladder if you have one, trim rails etc. Those screws want to back out and leave an entry point for moisture. All screws anywhere on the trailer can cause an issue and some, barely backed out, are hard to see but will cause issues. I have all kinds of tool boxes all over the place and I think the one tool I have the most of is the square drive screwdriver; just carry one with me around the trailer out of habit checking screws....