I would start with a clean image if you have run the installer part from Waveshare.
next add to /boot/userconfig.txt
dtoverlay=vc4-kms-v3d
dtoverlay=vc4-kms-dsi-waveshare-panel,7_9_inch
I would start with a clean image if you have run the installer part from Waveshare.
next add to /boot/userconfig.txt
dtoverlay=vc4-kms-v3d
dtoverlay=vc4-kms-dsi-waveshare-panel,7_9_inch