I paid my subscription and my service was still cancelled

1. Check the subscription status at Services & subscriptions. Sign in with the Microsoft account used for the Microsoft 365 purchase and look under Microsoft 365 to see whether it shows Active, Expired, or a past-due state.
2. Check the payment method at Payment options. If the old card is still associated with the subscription or the payment method shows an error, update it.
3. If there is a Pay now option on the subscription, use it to clear any past-due balance. A paid charge in the bank account does not always mean the subscription status has fully updated yet.
4. If the subscription now shows Active, close all Office apps, restart the device, and sign back in. If Outlook or Office still says the subscription is cancelled, the payment status can take up to 24 hours to sync across Microsoft services.
5. If the subscription does not appear under that Microsoft account, the charge may be tied to a different Microsoft account. Check the subscription under any other Microsoft accounts used for Microsoft 365.
6. If the subscription was bought through a third party such as Apple, Google, Amazon, or a retailer, billing and renewal must be managed with that provider directly. Microsoft cannot cancel, refund, or modify billing for those subscriptions.
7. If the subscription shows Active but the install or service access still does not work, contact Microsoft Support.

References:

• Problems renewing a Microsoft 365 subscription
• Manage my Microsoft 365 subscription
• Office error "Account Notice: We've run into a problem with your Microsoft 365 subscription"
• Use a screen reader to manage your account billing and subscriptions
• Why am I still getting 'account problem' notices for Microsoft 365 after updating my credit card information and paying for my subscription? - Microsoft Q&A
• My Microsoft 365 Subscription Reactivation - Microsoft Q&A