IG price movement not matching the dax this afternoon. VERY strange!

[displayname2022]

This afternoon, i placed a short on the dax, the price fell and as usual, the real world price movement matched exactly to the ig overall movement. 

Until at one point, the dax starts nosediving, the nosedive lasted around 6 mins and was a solid few percent. I then check back to the ig position screen and somehow my profit is decreasing! while the dax keeps falling further and further. 

Looking at the ig chart, the price was indeed increasing, while the charts on all other major sources were showing a continued decrease.

Before joining IG i did read about some funny business, but i find this really hard to swallow.

 

I can imagine IG want to say " well it doesn't match the market precisely " im not asking for precise, im asking for IG to follow the trend.