Earlier this afternoon before the GBP CPI, I placed a Pending BuyStop Order at 1.31790 but after the CPI data was released and the price moved, suddenly in MT4 my Pending BuyStop disappeared and Exness automatically replaced it with a Buy order at 1.31972.
Automatically in this case, I suffered a lot of losses because the profit that I should have made was reduced.
My question is, is this a common occurrence when there is a New release and a Pending Order, or should this not have happened, Min?
Thank you
@ For Honor:
That means you experienced slippage. At the time of the UK CPI release, your price order did not exist, so the price jumped directly from 1.3168 to 1.3200, as seen on the following GBP/USD 1-minute (M1) chart:

Slippage often occurs during high-impact data releases.
Read also: Don't Underestimate the Impact of Slippage, Be Careless and Immediately MC!
To avoid slippage, we recommend not entering before or during high-impact data releases, as volatility is high. Wait a moment until volatility has normalized and the price sentiment direction is clear. Trapping-style pending orders (buy stop and/or sell stop) before high-impact data releases are very dangerous, prone to slippage.