> For the complete documentation index, see [llms.txt](https://docs.trade.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.trade.xyz/support-and-faqs/faqs/orders-and-positions.md). # Orders and Positions #### Why was my order rejected? If an order fails, read the error message closely. It usually tells you the reason. The most frequent causes are hitting some limit (OI cap, size too low, etc.) or not having enough margin. #### Why can I not open a new position? When a market is popular, you might face an open interest cap. This is frustrating, but acts as a general safety limit. You can try a different market or wait. #### Why can I not place this order? Check to ensure you have sufficient funds in your account and are meeting appropriate tick or lot size requirements. These ensure orders adhere to market parameters. For example, if a perp has a tick size of $0.5, you can’t place a limit order at $30000.25, it must be $30000.0 or $30000.5, etc. #### Why does it say I don’t have enough margin? This can occur if the market moved and your available margin decreased or if you’re trying to over-leverage. Always keep an eye on your Available Balance in the trading interface. It’s good practice to leave a cushion rather than using all collateral as margin. #### Why did my post-only order not submit? A post-only order will cancel if it would match with an existing order on the book (because that would make it a taker order). Sometimes fast market moves or your own misunderstanding of the best bid/ask can cause an immediate cancel. Adjust and try again if you really want to place a post-only order. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.trade.xyz/support-and-faqs/faqs/orders-and-positions.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.