Defraggler won't stop computer from going into Sleep mode

I have two physical drives in the system. My computer Sleep time is set to 20 minutes. I started to defrag the non system drive. The de-fragmentation was at 40% and the computer went into Sleep mode. Defraggler didn't stop the computer from going into Sleep mode. I think this behavior should be changed.

I agree. Recently switched from Auslogics which has a "shutdown" setting that overrode the sleep setting which permitted the process to proceed to completion. I guess one has to change the power settings each time Defragger is run or go back to another program. Obviously shutdown and override sleep can be done because other programs have these features.