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The problem with your algorithm is that it's placing way more orders than you think. handle_data() runs every minute, so once your content.track hits 5000, you start placing an order every minute. The order is too big to fill in a minute, so you're in this runaway situation where orders are being placed on top of each other willy-nilly without your portfolio ever getting to a stable state. One way to handle this have sell_it_allcheck for open orders and exit if there are open orders present.
A better way to handle it, though, is to get in the habit of using the Optimize API. With optimize you pass in your desired portfolio and your constraints, and the API does all the order management for you. You avoid all of the annoying order management stuff like you're running into here. I'm attaching a backtest that looks mostly like your code, but changes the order method.
Note that in this algo we're still doing all of the ordering in handle_data which isn't recommended - you should put it into a schedule_function and run it daily or something. But for the sake of this example I left it alone.
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