Axitrader - Limit order filled at worse price

Hi all,

today i noticed that my limit order was triggered in worser price at XAUUSD. As i know its not possible to get worser fill in limit orders. This broker is FCA regulated and I wonder if its ok by the regulation? I contacted with the broker and they told me they do slippage on both positive and negative ways on both limit and stop orders. I worked in this sector before and in real market it is impossible to get worser on limit orders. If i make a complaint to FCA, do you guys think it works?

And here is the screenshot

I have axi account also,sometimes my trailing stop doesn't work.so we should raise where we think we have reasons.

I trade with them for a long time too. Also I understand their back system. It just triggers the pending order right after the trigger price from where it can find. This is acceptable for stop orders but limit orders should be different. In many countries limit order defined by the same. In the screenshot SEC also say what i say. The reason of why they cant fill my order from the price or better, is because of they dont Abook my orders. I think its Bbook and they fill in the background of MT4.

Ok you arent trading on an exchange so those rules dont apply.

But here is how the system works.
Your limit order is triggered on price check first via the bridge if you're using MT4
It then goes back and executes so if the market has moved then you will be slipped negative or positive or at the rate.
You may get a better fill on B-book as the order doesnt go to through to the LP .
But if youre a B-book client the broker has determined you as a loser ( no derogatory remarks intended) and will bet against your trading.