U2422HE, two daisy chained, suddenly being displayed as one

I have two U2422HE monitors connected to my laptop. One is directly connected via USB-C with MST enabled, the other is daisy chained DP to DP.

Up until yesterday, everything worked fine and I was able to extend desktop across all three monitors (incl laptop screen). This morning, I turned on the laptop and the desktop is mirrored on both monitors. This was slightly weird. I then changed to extend desktop. Now it shows both monitors as one single entity and both show the same.

Any idea what happened here?