Pretty sure a limit order is the limited amount you would take for it. For TDA it will say stop loss. Pretty sure you went with a minimum price amount instead of a market value, so you basically just sold it outright.

You entered a limit order, instead of a stop limit

Yep. TLDR you should have chosen “Stop Loss”

Sounds like it sold above the price you wanted. Probably should a set a stop loss instead. I highly doubt Fidelity doesn’t have a stop loss option.

I do not see a stop loss for after hour trading on fidelity, does anybody? It seems they only allow limit order and nothing else

Fidelity only lets you do Buy/Sell Limit orders in Pre/Post Market. Also, those Limit orders expire at normal market time, they will not carry forward into the day session. Post Market does not carry into Pre Market either. Stop/Trailing are only applicable to normal day session. When you set your Limit with a lower price to sell - it of course will sell through/down to that number and will execute anywhere from Market price to your Limit price. The Sell Limit price is the least you will sell it for…. Perhaps if Fidelity gets a few H100 Chips - they can have good till cancel Stop/Trail orders flow through all sessions….