Hi
Thanks for reaching out to Microsoft Q & A Forums .
Regarding your question , The issue might be a current existent Azure AD for your work domain ,
Following document covers most of it , Please do work with your IT department and drive this further :
https://techcommunity.microsoft.com/t5/azure-active-directory-identity/cleaning-up-the-azuread-and-microsoft-account-overlap/ba-p/245105
Also refer the below to create an account with new email ID and then work with Billing/Support team to link your subscription with domain :
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/troubleshoot-azure-sign-up
Thanks,
Pradeep