Hi @Riette Fourie ,
When you create MSTeams or Contact Group in MSOutlook, an associated SharePoint Team site will be created automatically that serves as a document library for that team.This is by design and unavoidable.
Here is a thread similar to your requirement, please check it out: TEAMs Team - without Sharepoint Teamsite?
Either way, we won't be able to disconnect the group and the SharePoint team site. The group must be deleted before the site is deleted, if you try to delete the group, the team site will also be deleted, this may take a while.
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