Hi @Carola7, let me see if I can help out here.
I have translated your question to English as this is an International forum, please post any replies in English and it will be easier for me and other users to assist you.
Have you tried clearing the data for the camera app? This will not erase any previously taken photos or videos, but it will reset all settings for the appwhich might do the trick. Find and tap Settings > Apps & notifications > App-info > Camera > Storage > Clear data > Tap "OK" > Restart the phone. Also, try testing the camera in the support app. Find and tap Settings > Support > Xperia Tests > Camera.
Another thing that you can try is to reboot your phone in safe mode to see if the camera works better there. All apps downloaded from Play Store is temporarily deactivated while in safe mode, by doing this, you can see if this behaviour is caused by a downloaded app. For more information on safe mode and how to use it, click here.
If the camera behaves the same way in safe mode, I would suggest that you try to repair the software on the phone using Xperia Companion and a computer. Keep in mind though that all user data will be erased by the repair, so it is advised to do a backup before to avoid data loss.
Try these measures and feel free to keep me posted with the results!
