ID Protection for Namecheap domain registrar module
The current Namecheap module does not support automated ID Protection management, yet their API does. WHMCS currently displays this message on the domain management pages of Namecheap domains in the admin area: "ID Protection cannot be managed automatically with the selected registrar module. Any changes will need to be made at the registrar directly."
The ID Protection should automatically be renewed when the domain is renewed, if ID Protection is enabled.
Namecheap API docs for WhoisGuard (i.e. ID Protection)