Sell/Stop Problems - ThinkOrSwim

Hi everyone, I have been paper trading for a couple months now. Trying to implement what I have learned through reading and YouTube videos. I have been fairly successful at predicting breakouts and whatnot. However, it is frustrating that when I am up and want to sell my position, my order never gets filled. So eventually stock retraces back down to baseline, or worse, I settle for a loss. As you can see in the picture, I am placing my sell order below most bid prices so I'm unsure why I don't get filled. Can someone please help me out with this?

Thank you so much,

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