Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello,
You will have to decide which one you want to keep and cancel.
If you want to cancel the one via Microsoft, Please go to https://account.live.com
Sign into your Microsoft account. Then go to Services. Click on Manage for the subscription plan you want to cancel.
Then use the following method to contact billing support.
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 detail step by step instruction with screenshots I posted in this thread: https://learn.microsoft.com/en-us/answers/c/2714817
If for any reason you don't see "Contact support" option right away, but you see the AI support assistant button instead, you can start the chat, let the assistant know that you need to chat with support regarding billing isue. It will ask you some questions, you can answer them, but if insist that it doesn't resolve your issue when asked, and insisted you still need support. It should eventually give you the Contact Support button.
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If you want to cancel the one via Apple, you need to cancel it from your Apple account on Apple's website, and contact Apple billing support for refund. Microsoft explains it here: https://support.microsoft.com/en-us/account-billing/manage-your-microsoft-365-subscription-purchased-through-a-third-party-44749f45-4c0b-5d41-a73f-7634b8d2a763