Hi @SAN SHU GONG
Regarding your issue, I’d like to clarify one point that may help provide some context. When you first purchase Microsoft 365 Business Basic, Microsoft automatically creates a default business account in the format username @ yourdomain. onmicrosoft. com, which is associated with your Microsoft 365 tenant.
To better understand your situation, could you please help confirm the following:
- Can you confirm with me that you have tried accessing Microsoft 365 admin center using the onmicrosoft.com account like this [username]@xxxx.onmicrosoft.com and it didn't work? Perhaps provide a screenshot if possible
-

- Did you create a business account (e.g username @ yourdomain. onmicrosoft. com) that matches with your personal account?
Hope to hear back from you soon.
The initial response may not fully address your needs, but it will help me better understand your situation. Once I get the information, I will try my best to find the next steps.
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