Bug#1010576: Fixed!

[gis-w@leonde.de]

I don't know what fixed it, but it works for me again:

akonadi-backend-mysql                         4:22.04.3-1
akonadi-server                                4:22.04.3-1
kontact                                       4:22.04.3-1
libkf5libkdepim5:amd64                        4:22.04.3-1
libqt5sql5-mysql:amd64                        5.15.4+dfsg-5
mariadb-server                                1:10.6.9-1

Thanks a lot to whoever fixed it! <3