Issue with 3.0.4 on watch. Is there an official place where to report Testflight app issues?

My 3.0.4 Tesflight version gives problems on my Apple Watch.
I am unsure where to report these issues.
But after all, when I start the 3.0.4 version on my Apple Atch Ultra, then the screen starts blank. Then I try to sync settings and get back to the main screen. After several attempts sometimes the mainscreen shows a fraction of a second and dissappears again (or maybe its just the time that solves the blinking). This keep repeating all the time. No constant lighting mainscreen.
I installed Testflight version 3.0.3 again and this problem is solved. The Apple Watch screen stays on again and displays ok.
Oh, an older version has the same problems. Tried 3 previous builds and all the same.
I think the sitemap is reloaded all the time. When I leave the watch ‘blinking’ and swipe to settings screen and resync the settings, sometimes the blinking stops and the watch displays the sitemap fine.
When I however scroll down on the watch and wait a little time, the sitemap reloads and show the top items again.
When I leave the OH app on the watch and reenter, the blinking does not happen. But reloading after some time occurs (visible when not at the top of the sitemap and after some time scrolled back to the top).
It would not surprise me if it has soemthing to domwith icon loading. I use some built-in icons and some self added png icons. Not all icons are displayed all the times. Sometimes they appear and then disappear again.