Hi @BEWOTEC Marketing ,
What type of account are you using? Is it an IMAP or Exchange account?
Do you try to access your email from a web browser and see if there is a difference? If it works on the web, the issue can be caused by the corrupted profile, you can create a new profile and re-add you account.
In addition, check your email rules to confirm if you have created one that might have caused the email to move to another folder.
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