Thank you for your help. After watching the video, I was trying to flash the image via balenaetcher but I always got a warning, saying "Somthing went wrong. If it is a compressed image, please check that the archive is not corrupted." and then nothing. I wasn`t able to write it to the SD with balenaetcher so I took the raspbian imager but still not working.
Try it with Rufus.
I am using an Argon One V2 Case which hase a HDMI extension board. If I take the HDMI extension out the Recalbox 7.2 works fine. But still the hardware was working with the Recalbox 7.1 Verison. Is there a posibility to get it working again?
I don't have this case, so I can't test it, but, I don't see reports from other users with this case with the same problem, so there doesn't seem to be an incompatibility between the case and Recalbox.
Have you tested with the other HDMI output?
Have you ever tried doing a factory reset?