When I try to use a material it turns blank?

Well earlier today I downloaded a asset pack, it was free, but when I try to use them I can’t because they go blank, no matter which one I use.

have they finished compiling? have you tried building lighting? are they 4.18 compatible? and have you looked at the material graph to ensure that everything is connected and that parameters have been set?

Don’t know if compiling did complete or no, lighting is fine, they are compatible with 4.18, the material graph looks fine as well.