3419067 - Not possible to add a Contact in the Contact facet of a Lead

You are trying to add a Contact in the Contact facet of a Lead but the add button is missing, despite being made visible in Adaptation Mode. 

SAP Cloud for Customer

The Lead in question has the status converted.  It is not possible to add Contacts to Leads that have already been converted.

This is the expected behaviour of the system.

lead new contact, add contact , KBA , LOD-CRM-LM , Lead Management , Problem