Unable to find a Destination model configuration equivalent

Hi, apologies if this is the wrong place to post as I'm first time poster.

In a recent reconcile of a model branch into a main trunk the following conflicts were identified. Has anyone seen the 'Unable to find a Destination model configuration equivalent' conflict before and what the issue is?

In checking the reconciled model, the five items, which are Use Cases, all look ok so i cant identify the issue.

Thanks in advance for any support,

Tom