This morning I got an announcement, that the new version AcyMailing 6.18.0 was available. The upgrade process caused an error (I do not remember the exact error message). The new version could not be installed. But this error caused my website to not being available any more: on the home page there is the following error message:
1054 Unknown column 'type' in 'where clause'
In order to make my website work again, I disabled all Acymailing items in the extension manager. The issue is probably caused by the AcyMailing subscription form module that is placed on the home page.
By the way: I am using Joomla 3.9.22 and I tried to upgrade form Acymailing 6.17.1 to 6.18.0.
Thank you and kind regards
Chris