Configuring motor at closed loop mode

I'm using FBL2360T and I'm just able to run the motor using the syntax serial in the console (I just could make the motor rotate using the command !S) in open loop mode, when I configure it to to any closed loop mode it doesn't work, even when I tried to change the loop error and using a lot of variables (RPM). What am I missing here? And why wouldn't any other runtime command work on my motor even in open loop?

Thanks in advance