Service event message.
Below the message is every 20 seconds active.
How can not active the this message?
Try re-running OPC configuration from Fieldbus management aspect. Sometimes it fixes this problem.
To solve it completely you would need to remove this file from FSD. There is tool deep inside fieldbus builder PH to do this job. I think it is call FBBfiletester or something like this.
However using this tool can be dangerous to system, so contact support if PH OPC server reconfiguration does not succeed.