When the following conditions are met, a group conflict will trigger.

• The provisioned group name matches an existing group with the same name on the target Atlassian site.
• The existing group contains a different set of members compared to the members in the provisioned group. 

When a conflict occurs, the admins need to resolve them manually via the org administration (see document). Admins can only resolve conflicts 20 at a time and this requires a lot of manual work when resolving a large number of conflicts (ie. 1000+).

Suggestion : Ability to resolve group conflict at scale.