After LDAP integration django.contrib.contenttypes.models.ContentType error

[HtHNightwolf]

Dear community,

I set up Netbox on Ubuntu server 22.04 LTS following this how.

When everything worked I took the LDAP integration tutorial and followed that aswell but now I am stuck with netbox not starting. I seem also unable to find anything userful by googling:
RuntimeError: Model class django.contrib.contenttypes.models.ContentType doesn't declare an explicit app_label and isn't in an application in INSTALLED_APPS.

Can anyone help?