Of course you can sell it now!!
Does it still have 2 years of the NHBA warranty left on it? That's an advantage, if so, and it should be mentioned in the advert.
Where do you park? If there is parking easily available nearby, the estate agent should say something like (right down the bottom of the advert) 'the vendors have no problems parking on the estate' - as long as that's true.
Secondhand new builds are a mixed bag. I'm currently looking at one (due to a good location) that's priced about 32k under inflation-adjusted market value, so they've already priced it low (300k), but it's BLAND. They've left it exactly as it was built, with a functional but unsophisticated kitchen, basic bathroom hardware with those horrible brown tiles that were popular with developers, and it doesn't exactly inspire me to want to rush to view it. It's been on the market since January; they haven't really added any value by not doing anything to it; it's only 13 years old but already looks horribly dated.
Have you made any improvements to yours? That can be the difference between a house flying off the market or one sitting around forever, because it has something that all the others do not.
If there are many others on the market, you need to price it much lower than them all to attract interest.
Put your postcode into houseprices.io and hover over your house; it will tell you the inflation-adjusted value.
Remember that new builds are often 10% more expensive, and you might still have to take 5-10% off that to get the price people are actually prepared to pay.
The other thing to bear in mind that I find with second-hand new builds - at least at present - is that they're often in areas where people continue to build. So you might find new builds are going up in your area for only 10-20k more than you want to sell yours for. What's a buyer going to do, fork out another 20k and have shiny new kitchens and bathrooms and a 10 year NHBA certificate, or buy yours?
That's why it's important to look hard at the competition and price it really keenly.