Create Material Blend is not working

In Unreal 5.4.4 I have been trying to use multiple Megascans in Quixel to make new textures/material instances/blended materials. Whenever I try selecting multiple material instances and hitting ‘Create Material Blend,’ it says “Current Material Blending setup doesn’t support more than 3 material instances.” I’m only using 3 material instances. I created a blend material out of a singular material instance and tried manually adding the other 2 instances to the middle and top layer, but that did not work either.

Please help, and let me know if you need additional details to do so.