Listen, this is what you need to do.
Assuming you are in Performance mode. Which you should be for this operation.
Also, assuming you have a rig loaded into Slot 1
First send MIDI CC 47 with the value one number less then the Performance you are trying to access. For example you are trying to select Performance 21, send CC47 value 20.
Then right after you send that, send CC50 with a value of any value not 0, so send 127 or 100 or whatever.
If you want slot 2 use CC51 to send a value other than 1.
Slot 3 use CC52
Slot 4 use CC53
Slot 5 use CC54
OR
If you are trying to send Program Change(PC) messages remember a PC selects a performance and a slot, the next PC selects the same Performance with the next slot. But the numbering is weird. ie PC10 selects Performance 3 Slot 1, PC11 selects Performance 3 Slot 2, etc. If you don't have a rig in every slot, incrementing the PC value will not do anything until it gets to the next Performance and Slot 1, in this case PC15 selects Performance 4.