I am not sure what happened but the Government originally started investigating United's tax situation a decade ago. It is not clear if anything has been settled privately or if this is still ongoing. I don't think they have paid any significant taxes in the UK for decades. Presumably they pay business rates to Trafford Coucil but, apart from that, they have invested virtually nothing in the local community for decades either.
They have the Manchester United Foundation which is a charity which is independent of the club. This charity, gets a small subsidy from the club, but most of its income comes from fund-raising on the back of the United brand. Nothing wrong with doing this but the fact is that MUFC itself invests virtually nothing in the Greater Manchester area. It is however very good at running PR gimmicks and the media never challenge them.