I have contacted the IG helpdesk on several occasions about the lagging of volume bars for most major US shares and have received different responses ranging from suggesting it is my internet connection or browser, to admitting the problem (9 days ago now) and saying that it is being looked at by the IT department,   However, the problem remains and prevents proper scalping of the US shares affected, including Tesla and Apple, as well as more than a dozen other shares I have tried.