Bugs with shadows on a rigged character

Hi
faced with the problem of incorrectly displayed shadows on the character
because of this I can not pass the test in the marketplace

the model looks normal if you look at it in a preview of the mesh, or a preview of the skeleton. If you exclude shadows in the scene, then everything is fine too.

But as soon as the shadow appears, and the animation appears black shadows filling some polygons entirely.

https://epicgames.my.salesforce.com/sfc/p/#1a000000L44R/a/1a0000005Ipu/f3htQbfgbKlOJQrCvsquZ2aVg1zCJG98kanZpdpmJOw
https://epicgames.my.salesforce.com/sfc/p/#1a000000L44R/a/1a0000005Ipv/MvacP.S3lOzK5yYPMbumyVv57.24rVYmtl4BIHrV0po

With the normals on the surface of the mesh everything is fine. There are no bugs.

If you rotate the model face to light, the artifact disappears.
if you move the camera back, the artifact also disappears.
In a scene with less sharp shadows, everything looks good

Please help to solve the problem.
thank you in advance