Failure to enter preselect mode

Good morning house.
The unit failed to enter preselect mode after it has been synchronized immediately the breaker closed then when about to increase the load to like 10mwatt then in 2 to 3 seconds the breaker will just open.
What could have caused that.

Gas turbine frame 6b to be presicely
Hi Akin,

What did you observed during just after synchronisation...i mean did the unit take the minimum load to avoid reverse power (Like 5 MW for example)...

Also any alarms (Diagnostics/process ) have been annuciated during this SOE..?