Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello
If you are running Ventura, you should be able to install. You just need to install a lower version.
Microsoft 365 can run on macOS Ventura 13 only by using an older Office version.
Microsoft ended support for Ventura with Office version 16.101, released in September 2025. Newer Microsoft 365 installations and updates require macOS Sonoma 14 or later.
Uninstall your current Ms365, then downgrade to version 16.101 by using this installer.
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However, if you still want to return and get a refund anyway, you need to contact billing support. It cannot be processed via the public community forum here.
Go to https://support.microsoft.com/contactus, Type "Billing" and press Enter. On the next screen, click "Contact support" at the bottom of the page, then choose "Microsoft 365" > "Manage my subscription". You’ll then see the option to chat with a Microsoft support agent who has access to your account to help review the issue.
You can reference this detailed step-by-step instruction with screenshots I posted in this thread: https://learn.microsoft.com/en-us/answers/c/2714817