Parallel approval behavior not working

Summary: We have used parallel behavior(using separate geo wise rule set) for one of the representative types which is not working as expected.

Content (required): Current flow is Manager Hierarchy> Representative. There are 5 incumbents in this responsibility type. The expected behavior is the approval should flow serially in a manager hierarchy followed by parallel behavior in representative. All 5 incumbents should get approval notifications however any one of them can approve and that would complete the approval chain.

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