このアカウントはすでに別のSpirアカウントで利用されています、というエラーが出る

This error message occurs if you are trying to connect a Google or Microsoft account calendar to a Spir account, but there is already a Spir account that has that calendar connected to it.
If you are using the wrong account to log in, log out and try again.
If you have linked the calendar to an account that you can no longer log in to, or if you have created multiple Spir accounts and want to consolidate them into one, you will need to cancel your Spir account.
To cancel your account, please contact chat support and provide the email address of the account you want to cancel.