Wash & return and say it was a mistake.
Then let us try and help you sort your financial difficulties?
I live in a very deprived area, there are several free Facebook pages with people frequently giving away all sorts. From clothes & unwanted gifts (often toiletries) to furniture and even flooring!
I was in your EXACT position last year. I got my living room suite, armchair and other bits and bobs free on our local one. The chap who runs it is fab, knows who's really struggling and discreetly puts them in touch with people who can help or "advertises" "someone in need [ie anon] - can anyone supply X y z?" He collects & delivers too bless him for those who can't afford man and van. He and others are also helping out the local homeless street sleepers get hot meal at least once a day - bargaining with local businesses that if they'll donate he'll promote their business on the page. Good publicity for them, food for homeless.
The schools & foodbanks here give clothes to those in need.
There's also freecycle and gumtree.
Also are you getting everything you're eligible for? Is your child? Have you cut back wherever you reasonably can?
Joining a credit union is a great idea, also look on mse for advice on getting reputable loans (Provi are legalised bloody loan sharks frankly!) from various sources.
Do you have anything you can pawn or sell?
CoughLaughFart - unfortunately especially this time of year there are sometimes threads posted by unscrupulous posters claiming hardship. Not directly asking but banking on the kindness of posters and taking advantage of that. I'm. I'm not at all saying that's true of op but it would be remiss of mnhq not to urge caution.