Hi ND. I'm Greg, 10 years awarded Windows MVP, here to help you.
Try these fixes for Switch User missing in WIndows 10:
https://softwarekeep.com/help-center/no-switch-...
https://winbuzzer.com/2020/08/21/how-to-enable-...
https://thegeekpage.com/switch-user-option-miss...
https://www.youtube.com/watch?v=TrJ3r_ot8cE
Feel free to ask back any questions. Based on the results you post back I may have other suggestions if necessary.
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