We are not seeing the option 'Generate Document' as self-service while we have activated People Profile and also granted permission to 'Generate Document as ESS' (or 'Generate Document as MSS') under 'Manage Document Generation' in the role.
Reproducing the Issue
Goto Employee --> My Employee Files --> Take Action. 'Generate Document' option is not available.
The role for the suer does not have permission to 'Update employment records (displayed as 'Take Action' button)' under Employee Data > HR Actions in the same role.
Update the role to also have permissions to 'Update employment records (displayed as 'Take Action' button)'. Below is the screenshot for reference.
KBA , LOD-SF-EC , Employee Central , Problem