You have to assign the switches to a function in FM3 Edit and tell the FM3 what switch you have there in the Setup Menu
Here my notes for a reset:
Setup Menu
FCControllers/Onboard Switches
Stand-In-Switches:
FM3 SW2 TIP: Layout 8: Utilities - Switch 6: Layout, Inc/Dec
FM3 SW2 RING: Layout 8: Utilities - Switch 4: Scene, Inc/Dec
Setup Menu
I/O:
Pedal:
Pedal 2 Setup:
2 Switches (Tip+Ring)
Switches setting:
Switches Behavior - Follow Hardware
Polarity - Normally Open/Momentary Make
FM3 EDIT
FC Controllers