We do have multiple people using the Jira Cloud for Excel plugin.
We use different Jira Filters to get data frol Jira - that's working
But when we select the Fields in the Import Data for Jira window they are overwritting the fields used by other excels.
Is there a space where the fields list is stored?
Sadly, these are known problems with the Jira Cloud for Excel plugin and not the only one you can run into when using it and many of them have no solution. If you'd like to export to Excel, try Better Excel Exporter, it is stable, customizable and has many default templates for various use cases. If you have any questions or problems, ask our support!
(Please note that Better Excel Exporter is a paid and supported app and I'm part of the team developing it.)