Rodabod mentioned g springs, this is the most likely cause of your shifting problem, these are in the shift levers and are a pain to replace, but doable if you follow instructions carefully (YouTube). Parts can be got from Downland cycles.
@petertreglown started
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Rodabod mentioned g springs, this is the most likely cause of your shifting problem, these are in the shift levers and are a pain to replace, but doable if you follow instructions carefully (YouTube). Parts can be got from Downland cycles.