Hi @Pitsanu Polsri,
Welcome to Microsoft Q&A forum.
Thank you for reaching out. I understand how difficult it is to repeatedly attempt purchasing Microsoft 365 Business Basic only to receive the message “Something happened. Validation of your order failed.”
This issue typically occurs when Microsoft’s automated verification system cannot complete the required checks during the order process, or when there is a temporary problem with browser sessions, account details, or payment validation.
Based on what you've described, this issue likely involves your billing profile and subscription records, and will need to be reviewed by the Microsoft Billing department to ensure everything is correctly linked and processed.
The best next step is to contact the Billing team directly through the Microsoft 365 Admin Center. By following the steps outlined below, you can easily submit a support ticket and get the assistance you need to resolve the issue.
1/ Log into admin.microsoft.com with your admin credentials. If you don't have admin permissions, you'll need to contact someone in your organization who does.
2/ Select the green help & support button typically located at the bottom right of the admin center dashboard. Click on it to open the support pane.
3/ Type in “I need to purchase Microsoft 365 Business Basic but the order keeps failing” into the search bar.
4/ Select “Contact support”.
5/ Choose your preferences: preferred contact method, preferred time zone, and preferred contact language.
6/ Fill in your details and give a strong description of your problem for a quicker resolution. You can add a file, a screenshot, or a video for added support. Once you’ve filled out the details, select Contact me at the bottom.
In case of urgent, you can also reach Microsoft Support directly by phone: Customer service phone numbers - Microsoft Supportand select your country/region own phone number for support.
We truly appreciate your understanding as we do our best to support you here. Please note that our ability to assist with billing-related issues in this forum is limited, as we don’t have access to the secure, account-specific tools needed to make changes to payment methods or view subscription details.
I hope this information helps. Please try the steps and let me know whether they resolve the issue. If the problem persists, we can work together to find a solution.
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