By Bethany Wales An uptick in people toasting West End night outs with a glass of fizz failed to boost profit at the UK arm of bubbly producer Champagne Lanson, according to newly-filed documents. The firm, whose French parent company has been making Champagne since 1760, saw its sales volumes fall by four per cent in 2023, although a nine per cent increase in its average sales value helped it to grow its turnover to £45m from £43m in the year before. Lanson said the reduction in sales volume was despite what it described as “buoyant” hotel activity in London’s West End, with events like Wimbl…