In case you notice any issue with Merged Leads – Parent lead is not showing up when you Advanced Search or have a Dynamic list based on an Activity done on the Child lead – though the child leads activities are reflecting on Parent Lead;
This could be due to it being an ESS enabled or big tenant. So this happens due to Activities not getting pushed to the ESS from where the Adv Search results or dynamic lists’ leads are fetched.
Hope this helps.
