If you have been charged twice for the same service, you can request a credit for the duplicate charge. To do this, you should contact Microsoft support directly. You can log in to the Microsoft 365 Support and submit a ticket regarding your billing issue. Make sure to provide them with the details of the charges and your account information so they can assist you effectively.
Additionally, if you have any specific preferences for how you would like the credit to be applied (e.g., refund or credit to your account), be sure to mention that in your communication with support.
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