thanks, yeah I tested with a multimeter and it indicates the switch is working, someone else suggested due to the keyboards age the main chip is probably dying.. I'll have another look at it when I have time but purchased a KeychronI'm happy with
sorry for the late reply, I'll have a look at the diode, I didn't try flux yet either but seemed like there was enough in the solder I used.. another guy suggested that due to age etc the issue is probably more central and its time for a new keyboard. I purchased a Keychron in the meantime, really happy with it