Diagnostic WatchDogOn and ExtDiag on Profibus - AC800F

We've recently upgraded our AC800F system to have a redundancy profibus connection from controllers to CI840 clusters (using RLMs).

After the upgrade the system seems to be working fine, but we get the "diagnostic data present" (in the "standard diagnostic" tab, WatchDogOn and ExtDiag are set true).

We've tried to increase the watchdog time (TTR is set to 300000tBit and baudrate 1.5MBit/s) to 250 (*10ms) without success.

Sometimes the diagnostic data vanishes when we reset the RLM modules, but that doesn't work every time. When it works, as soon as there is a toggle from controllers, the diagnostic data returns.

How do we solve the diagnostic issue?

Thanks!