Washing Machine hoses

[Tas_Dean]

Ring the 'delivery guys' boss and have them come and fix it for you.

I second that, and I'd hit them up for water damage also! They connected it, their problem.
Washing machine hoses are very easy to cross thread. Run them backwards a turn or two before doing them up, usually helps to make sure you have it on straight.

[wonderplumb]

Get the blokes back out who installed the machine. If they've managed to cross thread the plastic nut thats theyre problem. The only hassle you might have is trying to prove it. Wether the taps are 40yrs old or 5 mins old they still have the exact same thread, 3/4 BSP. If you must buy new hoses get the specific ones for that machine from the manufacturer.