Face missing when in cycles render engine

Hi guys! I seem to have some faces missing when I change to the cycles engine and I don't know why. I tried filling them but it doesn't do anything. Can you help me out pls? Thank you!
https://drive.google.com/file/d/1nw4IgsNM0TZX8HvdK_2cJGMyr_HT-jZm/view?usp=sharing

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  • Vue Thao(euv) replied

    Big help would be better if you upload a blend file on dropbox or google drive. 

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  • Dwayne Savage(dillenbata3) replied

    It looks like you have double vertices. Try using merge by distance. (in edit mode, press A to select all. Then M->By distance)

  • Martin Bergwerf replied

    Yes  Christian CChristianDior ,

    As euv already said, a link to your .blend would be helpful here.

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  • Adrian Bellworthy replied

    At the very least an image in edit mode so we can see the mesh.

    1 love
  • Omar Domenech replied

    Those black strips are probably not missing faces, but overlapping faces, they tend to create such artifacts. Also flipped normals. Or maybe those faces don't have any material applied. So it could be a couple of things. 

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