Setting up new computer and account showing not valid

Hello Rita Rita,

Thank you for reaching out to Microsoft Q&A and informed us about the issue, from your description It seems your device was setup using a personal account instead of a work account, the following is a instruction to tackle this issue:

1. Add a work account separately:

• Open Settings > Account > Add a work or school account > Connect > Input the work email > follow the prompts to link the device (However, this may not remove the personal account completely, but this will grant access to work resources and policies)

1. Switch to a local account:

• Open Settings > Accounts > Other users > Add accounts
• On the Login windows > Click I don't have this person's sign-in information > Add a user without a Microsoft Account
• Sign out of your employee's local account and sign in using the new account you just created
• Go to Settings > Accounts > Add a work or school account > Connect > Input the work email
• If you want to remove your employee's personal account, on the Accounts setting > Email & Accounts then click Remove

1. Reset the PC:

*(In case the above instruction can't solve the issue. However, once reset the PC it will completely delete all of the data in the computer along with all personal credentials. Please consult with your IT department before proceeds)

• Open Settings > System > Recovery > Reset this PC
• Follow the prompts then choose Remove everything

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Haytham - MSFT | Microsoft Q&A Support Specialist.