Hi @Romain Bisi
Currently in Microsoft Q&A we only support English, could you please edit your question into English?Thanks for your understanding.
Via translation tool, I get the following content.
Are you using Microsoft 365 Apps?
If so, please try the steps in article: Microsoft 365 Apps activation error: “Sorry, another account from your organization is already signed in on this computer”.
- Click Windows Settings (the gear icon) > Accounts > Access work or school. If the account you use to sign in to office.com is listed there, but it isn’t the account you use to sign in to Windows, select it, and then select Disconnect. Restart the device and try to sign into Microsoft 365 Apps again.
- Reset activation state for Microsoft 365 Apps for enterprise. Please download the OLicenseCleanup.zip file, extract the OLicenseCleanup.vbs script, and run it using elevated permissions.
Any misunderstandings, please feel free to post back.
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