A generic error occurred in GDI+ while running .NET Core app on Linux

i have a .NET Core app that runs fine on Windows. Recently we moved it to a Linux VPS and succesfully got it running.

Everything is working except whenever bitmap.Save is called it throws: System.Runtime.InteropServices.ExternalException (0x80004005): A generic error occurred in GDI+

This exception only happendes while running on the Linux VPS, not on our local Windows machine. I have no clue on what could be causing this and was hoping someone here might be able to help. It would be much appreaciated!