APE on E-Trade

When the aftehours market closed on Friday my e-trade account showed a significant increase in the price and a large gain as well. Today, I opened the app and all of the after-hours gain was gone and now its only showing the regular trading price and small gain. No idea what that means..just odd. $AMC Entertainment(AMC.US)$ $AMC Preferred Equity Unit(APE.US)$