A render problem of First Person & Decal

In UE5.5.4, there has been a new experimental function called “First Person” mainly used for Blueprint for camera and related models. However, when there’s a decal attached to a first-person model, it only gets rendered inside blueprint preview. When it comes to running the game itself, which means the camera that is being used is the first-person camera, in such case, the decal failed to get rendered. To go into details, it seems the decal itself isn’t where it should be, it gets extremely offset or to say, extremely deviated. I don’t know how am I gonna do with it to fix it. I just wonder that is this problem solved in later versions(5.6.1 & 5.7.4)? If so, I think I gotta transfer my entire project to a later version after downloading, and if not, I really wish the official developers would notice this and try to fix it, but for now, I’d be awaiting an answer.