This is a permanent market and its duration will be lengthened as long as it's allowed. The aim is to sell your stock (see the YOUR TRADES section next to the COMMENTS section) when you believe your side has over-corrected and buy in/short it again once it's over-corrected to the other side. Essentially, it's meant to function like a traditional stock market.

Read more: https://help.manifold.markets/manifold-101/why-would-you-sell-your-shares