Ron K's excellent website has the wiring diagrams for the Amazon. If you look at this wiring diagram it shows the flash to pass wiring which consists of the momentary contact switch on the steering column and the 'Relay For Headlight Signalling' which connects to the high beam.
https://sw-em.com/Wiring_Diagrams_an...Wiring_Diagram
Based upon the wiring diagram it should be pull the switch and the high beams come on and the high beams go off when you release the switch. Pretty much as Rustinmotion describes. If the column switch is sticking then the high beams would stay on; but, that does not sound like your problem. I am thinking that perhaps a previous owner got creative with wiring and might have installed a latching relay as used on the mid production 140 (which did not have the foot switch) and slightly botched the installation.
As per the factory wiring diagram the column switch should have no ability to operate the low beams and according to the wiring diagram the high beam flash is enabled 100% of the time. Time for some wire tracing and component inspection.