I've the same problem, I receive these annoying alerts every time a certain market is up/down by a certain % and I want to be notified only when positions are automatically opened.
I asked for IG support and they answered to check all those settings I've already checked and disabled on both old/new platform, without success:
Account –› Settings –› Notifications
Calendar –› MacroEconomic events
I then asked if those alerts are related to the markets that are on my watchlist
and I got an other vague and pointless answer:
It's not possible to target alerts bet