Hey Andy,
Is it a personal or business account Subscription? If it is personal check this page and steps to renew it - https://support.microsoft.com/en-us/office/renew-microsoft-365-for-personal-or-family-use-58f3d0f8-15c4-4ad8-8c5f-16d682e8b545
For Business - https://learn.microsoft.com/en-us/microsoft-365/commerce/subscriptions/renew-your-subscription?view=o365-worldwide
Hope this helps.
JS
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