NOTE: If two duplicates are in Marketo and only one is in Salesforce, the steps below will merge the two duplicates in Marketo.
Login to Marketo and Create a New List as RingLead Dedupe List (NOT a Smart List)
Create a New Campaign
Smart List “Added to List”. Set List Name to RingLead Dedupe List
Flow is RingLead Webhook
Go to Lead Database > Possible Duplicates > Leads
Click “Select All”
Go to Lead Actions > Marketing > Add to List