We had a Holiday Rambler travel trailer several years ago. It was essentially a "flat front" trailer. Fuel mileage was terrible until I put a "wedge shaped" cap on the truck. That cap not only covered the contents in the bed, it also redirected the airflow up and over the trailer. Fuel mileage increased almost 2MPG.
Your trailer is an "ultra-light" model. That means that the manufacturer has removed as much "bulk and weight" as possible from the trailer to make it towable by smaller vehicles. Typically one of the first weight cutting measures is to remove the luan backing from the FILON. It helps to "strengthen the rigidity" of the FILON, but adds significant weight. Removing the luan will cause the FILON to be much more flexible.
If you look at the airflow in these pictures, you can see "why" the air flowing over your tow vehicle pushes against the front of your trailer causing it to "cave in". It isn't a significant problem but if you don't like the looks of it, you can test different "rooftop additions" that might alter the airflow. One simple addition could be adding a cargo bag to the rooftop rack (if you're towing with a SUV) or a taller cap if you're towing with a pickup truck.
There are several "air dams" available that mount on the roof of the tow vehicle. Some of them are effective, some just add weight and don't do much for aerodynamics. They were very popular about 20 years ago when fuel prices were higher and people were looking for any means to reduce the cost of towing. Today, they aren't as popular, but are still available.
Your solution may be simple, or you may find that you have to go to "extreme measures" to redirect the airflow. On the other hand, you may find that it's just not worth the effort. It's pretty much your choice, but what you see is fairly common on ultra-light trailers with "floating" FILON caps.
2015 F250 6.7l 4x4
2014 Cougar X Lite 27RKS