Cucurella was viewed as the priority target before the transfer deadline, with a loan offer made by Manchester United. The deal was very close as an agreement was very close over a £3million loan fee, with personal terms already sorted but Chelsea purposely cup tied Cucurella in the Carabao cup game before loaning him out. I think Manchester United didn’t like the deal and decided to opt out for a new target, Reguilon.
Manchester United is ridiculously ask for low amount while Chelsea have sign Cucurella for high amount, it's make sense how Chelsea demand quite high rather than loaning Cucurella for small amount money.
Since Manchester United is really need a new player to replace their injured player, so they have no time to find a worthy player. As long as Reguilon can play in his position, not have to be good, I think it's already enough.