multivalue
No knowledge of Ameritrade. But sounds like the system working.
Limit orders dictate the price you will except, But your brokers job is to save you more and gain you more, if they can find a match, that will benefit you, above your limits.
So a good broker will close some sells higher then your limit and buys lower. Both doing what the broker is support to do, for you. Bigger gains & lower losses.
If they ever close a limit order which doesn't meet you minimums, you would loose more and gain less and you could go after them for that. But everyone is happy when they do their job and get you the BEST PRICE possible.
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