Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
If you purchased a Microsoft 365 subscription through the Google Play Store, not directly from Microsoft with your Microsoft account, on the link below, Microsoft indicate you need to contact Google Play Store Support to cancel the subscription to arrange a refund.
If that is not possible and you are unable to recover your Google Play account, the best option would be to contact your bank to cancel the associated direct debit for the subscription.