decal not covering entire surface

ok so i am having trouble with decal since it’s not covering the entire surface of my mesh as you see bellow

i have posted a question on the answerhub but it seems no one knows anything so please if anyone has any idea i would be greatful

the info i put in the answerhub thread:

ok so i have purchased the Top down sci-fi and i wanted to turn it into a horror type game so i started using blood decals the only problem is that the decal only covers the metal parts of the mesh surface. i know for a fact that the problem isn’t the mesh since when i used a black material on it the decal would cover the whole surface so it has something to do with the material

i am guessing the material of the mesh has several layers and the decal is covering one underneath please help i have been playing around with the material attributes and currently i have had no luck i even only connected the base color but that didn’t help also the meshes have two uv channels if that has to do with anything i would appreciate help alot! thanks!

i have attached two picture showing the problem as you can see the blood covers the metal part of the surface but not the surrounding panels!

Link to your AnswerHub Post: Decal doesn't cover whole surface of mesh - UE4 AnswerHub

Can you show the material setup for your decal?

Also, when testing try to use just a base color material on your mesh you want to place the decal. This can be a good way to debug anything that is going on by removing as many variables as possible. Then we can start adding things back in until the problem is found.

The two UVs are not going to be the problem. These are requirements for marketplace content. 1 UV for the textures and 1 UV for lightmaps.

I have the same issue where decal appears properly only when the material underneath is black or uses a metalness map (is metal).
Activating the G-Buffer solved the issue but still a lot of artifacts where decal disappears when you look at it from certain angles or you move around…

sorry i wanted to be able to test it and then reply i don’t have access to an optimal pc right now and it has shown non consistant behaviours for materials and decals sometime burring it and sometime displaying it correctly vut i thank you for your reply and will try your method to debug the problem and hopefully find a solution if not i will be back here with new info and updates

thanks again