Tab 400 2021 front window shade adjustment

you mean the lower shade is pulling the screen down when they are connected, or the screen on its own, not clipped to the lower shade, does not stay up?

Yes, thought as much, unclicking the two is an immediate solution, but even Snapped together, they should stay where you want them.  I would contact your dealer for a warranty adjustment here.  Start a warranty “punch” check list whist you shake the trailer down during initial summer use.  Then give the dealer a complete list of what needs to be adjusted/fixed, instead,of nickel and dime him over several little things.
cheers

@Giota, although I cannot locate the original discussion thread, I previously copied the below information, which may be of some assistance.  Since you have a 2021 model, it may not specifically apply to your window, but it does appear from your photo that you can pop off the lower corner of the window frame as depicted below.  (NOTE:  If you are not already doing it, while towing your trailer, keep all the window shades open.  This should help keep them properly adjusted.)

"There is a way to adjust the tension. If you look at the picture you will see a little screw that is circled in red. Pop off the little corner at the bottom of each side to access the screw.  There is a screw on each side of the window.  Tighten the screw to adjust the tension. 

There is a lot of information in this link as well."

https://onedrive.live.com/?authkey=%21AFBCFuVZQDMqKuU&id=6952E6E2E9104218%212174&cid=6952E6E2E9104218