I purchased the home in Whiterun as well as all decorations. But the alchemy laboratory won't show up in the house no matter how many times I buy it. The line of text "Alchemy laboratory (500 gold)" also won't go away after I purchase the item. Is there anyway to fix this glitch?

I play on Xbox 360 and I have Dawnguard installed. No other DLC is installed. I play using the most recent patch (1.8)