If you can’t use the footswitch connected to the AC-22LX to record with the looper, check the following points.
Mode and polarity switch settings for the footswitch
Set the footswitch mode and polarity switch as shown below.
FOOT SW CTRL ASSIGN
In the AC-22LX Editor, go to SYSTEM > FOOT SW/PEDAL SETTING, select “LOOPER” for FOOT SW CTRL ASSIGN.