Adds a HeldAccount to a hold. Accounts can only be added to a hold that has no held_org_unit set. Attempting to add an account to an OU-based hold will result in an error.
The URL uses gRPC Transcoding syntax.
The matter ID.
The hold ID.
The request body contains an instance of
If successful, the response body contains a newly created instance of
Requires the following OAuth scope: