Category Error, If I change a category in my inbox the email disappears, where do they go

Help emails are categorized and when i select none in category they just vanish, i can’t fine them anywhere, whats going on???

If you are using gmail, chack in “All Mail” folder. Gmail’s folders are actually virtual and are based on categories, so if you delete the category (specifically inbox), they will only appear in All Mail. When you find them in All Mail, right-click on the message, choose “Move to Folder” and highlight “Inbox”. They will again appear in the Inbox.