Wow thanks, I just need to spray my knob with WD-40!! 🤣🥴... I just gave the last try:
I pulled both knobs out and put just a spray of WD-40 into the holes, and now both knobs work perfectly like new.
@kptg it worked, hopefully I can drive back to the uk in summer, as I still have 50 bottles to return to Belgium, mainly Lambic (Faro) & Leffe.