Using simulation, after I bought a contract in a market, the chart stopped moving so that was a little concerning. I clicked "Sell" since I couldn't see anything and closed the program out and am checking with support on what more I've got to figure out with all this craziness.
I come back a few hours later and notice the Continuum demo account is showing a green number on unrealized PnL so I thought to click "Accounts" and select what was in there and "close".
It then audibly said order fulfilled and back on the chart i see a "Close".
So can someone help me understand the difference between the two? I guess I got lucky on this "trade" but this could have been bad if it was a real account and went down.

screenshot:

I dunno if this is your problem, but do you have any of this stuff checked off?

It's Under Tools -> Options


2021-02-02_172049

You bought 2 Lots but sell only 1 Lot, so you were still long with 1 Lot. At the end you closed the open 1 Lot long position.

ImActuallyStupid 

Using simulation, after I bought a contract in a market, the chart stopped moving so that was a little concerning. I clicked "Sell" since I couldn't see anything and closed the program out and am checking with support on what more I've got to figure out with all this craziness. I come back a few hours later and notice the Continuum demo account is showing a green number on unrealized PnL so I thought to click "Accounts" and select what was in there and "close". It then audibly said order fulfilled and back on the chart i see a "Close". So can someone help me understand the difference between the two? I guess I got lucky on this "trade" but this could have been bad if it was a real account and went down. screenshot:

ImActuallyStupid 

Using simulation, after I bought a contract in a market, the chart stopped moving so that was a little concerning. I clicked "Sell" since I couldn't see anything and closed the program out and am checking with support on what more I've got to figure out with all this craziness. I come back a few hours later and notice the Continuum demo account is showing a green number on unrealized PnL so I thought to click "Accounts" and select what was in there and "close". It then audibly said order fulfilled and back on the chart i see a "Close". So can someone help me understand the difference between the two? I guess I got lucky on this "trade" but this could have been bad if it was a real account and went down. screenshot:

Look at the quantities for each trade, as shown on the chart.

You didn't buy "a" contract, you bought 2 ("Buy 2 @ 13235.50"). Then when you sold the first time, marked by the arrow, you sold one of them ("Sell 1 @ 13284.75") . That gave you 1 left, as @Koepisch pointed out. Since you still had an open position (1 contract), when you hit "Close," it closed you out by selling that additional contract, with "Close 1 @ 13315.75."

The difference between the two is that you had lost track of how many contracts you had in your position. The final "Close" was also a final "Sell" that closed your position.

So, two things about this:

(1) This happens to everybody sometimes, leaving part of a position open because of a simple error. Probably when you clicked "Sell" the first time, you didn't notice that it had an amount listed, probably the default of 1. You probably assumed it was going to sell out everything. (I'm not using NT, but most platforms will have a button labeled something like "Flatten" or "Close All" -- that's your way to just get out without specifying how many to sell.)

(2) This simple mistake can be disastrous.

Don't worry about the fact that you did it, since it's on sim. But pay attention when you click that mouse. Those little clicks can be dangerous.

Bob.