If you believe your order was executed incorrectly, you can check on your reports.
On the reports tab, there are multiple sections that can provide an array of information that you can utilize in deciphering the details of any order.
You can learn more about the various order types and what to expect when each of them executes: https://support.bitfinex.com/hc/en-us/articles/115003451049-Bitfinex-Order-Types
It is recommended you contact us as soon as you see any disparity in the order because if a considerable time passes, our assistance might be limited. When you do so, please provide us with the relevant order ID and the reasoning as to why you think the order was wrongly executed.