Metahuman material problem

Hello,

I have finished designing my MetaHuman character. As you can see in the attached images, the character looks perfect in the MetaHuman Identity editor (MHI_Aris).

However, after I press the “Generate” button, the character’s skin textures fail to apply correctly in the Blueprint (BP_MH_Aris). The skin turns completely black, while the clothing materials seem to be working fine.

I have tried several methods to fix this but have been unsuccessful. Is this a known bug, or am I missing a step in the process? Any help would be greatly appreciated.