Error when trying to create/update tickets in new service (Onsite 10.2.9)

Hello, one of our customers have a problem with the new service in an onsite enviroment, everytime when they try to save a ticket in the new service does the creation fail and they´ll get this error.

MicrosoftSQL Server Native Client 11.0SQL ServerThe conversion of a datetime2 data type to a datetime data type resulted in an out-of-range value.

They can still create new tickets in the old service.

We tried the database on our local machine (We tried creating and updating tickets in the new service), and it worked there which was why we first thought it might have to do with user permissions.

We also thought this had to do with user permissions since we could get the ticket list but not create or update tíckets so we tried adding a new copy of the database with new user permissions but that had no effect.

We have also tried installing a new Sales&Marketing endpoint but that has not worked out aswell.

We have verified that the versions are correct in the SM/CS and the database.

There is also another issue when you first try to load in the tickets which generates a 403 error.

But when you choose a ticket in the list, the ticket information shows up fine.

Have anyone else encountered these problems before?

Regards
Fredrik