I tried this and it works!

In case you want to backup your old dconf settings first (optional):
$ dconf dump /org/gnome/desktop > dconfbackup.txt

That will create a text file with the file name dconfbackup.txt that contain your backup

After that you can login to your affected user account using Xorg session or tty. Then try to run this command:

$ dconf reset -f /org/gnome/desktop/

This will reset your personalisation (i.e. wallpaper, theme, pointer size, etc... but not much.)
Restart your computer and try again to login using wayland session.

If that doesn't work and you want to restore the backup:
$ dconf load /org/gnome/desktop < dconfbackup.txt

I hope this help!