Hi Erin,
Investigation on manual merges can be done both via UI and API.
From dashboard activity log your can search how many Profiles merged manually, once you navigate to individual record history facet on right hand side of the screen shows the timeline of merge, user details, match rules etc.
You can get the same detail via API : {{tenantURL}}/activities?filter=(equals(items.data.type, ENTITIES_MERGED_MANUALLY))
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Ashish Rawat
Manager
Fresh Gravity
Bangalore
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