You have a requirment to migrate Letter Activities but the Migration Template have few Labels missing
Reproducing the Issue
1. Go to Business Configuration work center
2. Select Implementation Projects view or Overview.
3. Search and Open the migration activity Migration of Letter Activities
4. Execute Migration for the respective Migration File
Migration of Letter Activites is not currently supported in Cloud for Customer
The activity Migration of Letter Activites will be removed from Cloud for Customer system in one of our future releases.
KBA , LOD-CRM-ACT , Activities , How To