SveinErik

I got this from their chat. 

Quote

Okay, to filter active accounts from unused accounts, you can tag active customers in the Customers panel. To learn more, visit our guide: https://support.squarespace.com/hc/en-us/articles/229497568#toc-add-and-manage-tags While we don’t have a built-in way to delete customer data, Site Owners can send requests to delete specific data to privacy@squarespace.com. The Site Owner is usually whoever started the site. You can check the permissions of every account on your site in the Settings > Permissions panel. We have more information in our guide here: https://support.squarespace.com/hc/en-us/articles/206537297

Send them a few emails, and we will probably get a built-in fix after some time.