I tried the following fixes, which didn’t work:
In the “installation” tab, disabled “Ethernet/IP Adapter”.
In this tab, I disabled the gripper. It’s not connected to the robot anymore.
I restarted the robot.
Lloyd helped me out. This problem was solved by disabling all settings in the installation tab (Ethernet/IP Adapter, MODBUS, PROFINET Onrobot FT Setup, gripper), saving this installation and rebooting the robot.