Blending Materials error

I’ve got a huge problem with blending materials in UE5.2. I’ve tried everything and nothing works PLEASE HELP IM DESPERATE. I’m new to unreal so maybe there’s an easy solution but I can’t seem to find it anywhere.
I had a typical ‘setup doesn’t support more than 3 instances’ so I tried to apply it to the active top and middle layer manually. This is not working either and the place where you’re supposed to drop the texture lights up red instead of green (see a screenshot).

Hi @m.bys! Welcome to the forums, we’re glad you’re here!

A workaround in regard to this issue has been shared here. Would you kindly check to see if this guide fits your needs?

Hi, thanks for replying. Unfortunately, I can’t apply textures manually as described in my first post because the frame lights up red and it won’t let me drop the material. I discovered that this issue only occurs while I’m in an Architectural set-up, the blending works perfectly fine in the Game world. I don’t want to start over with the whole project in Game just because I can’t blend so let me know if there’s something I could do to fix it in Architectural.