Today I updated our Master to 25.
First critical point was an update circle 24.7 -> 25.1 -> 24.7
I already had this behaviour on an other opnsense and fixed it:
If you enter at console pkg update you will see a segmentation fault.
Then you need:
pkg boostrap -fAfter this the update works as expected.
Ok, back to the problem:
In the GUI one OpenVPN server is marked red and it is not possible to start it.
In the log you can read ... device is busy
Solution was to kill the running openvpn task on the CLI.
Then it was possible to start the server in the GUI.