Quicken has not been resetting the cloud account appropriately when we restore a Quicken file backup (or open a different of a Quicken file with the same file identifier) for about a year. I hope they will let us know when they have addressed the issue but, for now, before opening another Quicken file that has the same file identifier embedded, I suggest you delete the cloud account.
Note: You need to open another Quicken file to delete the appropriate cloud account. You may want to review: https://www.quicken.com/support/how-edit-or-delete-your-cloud-datasets-quicken-windows The other Quicken file needs to have a distinct file identifier so that we may delete the cloud account associated with the original Quicken file. For example, you may create a new Quicken file (select File > New Quicken File...) without any accounts and enable sync in preferences so you may view and delete the cloud account associated with the original Quicken file.
Note: Only File > New Quicken File... generates a distinct file identifier. All other forms of creating a Quicken file, copy the embedded identifier from another file.