RevokeAccess.cs

/// <summary>
/// Revokes access to a shared record.
/// </summary>
/// <param name="service">Authenticated client implementing the IOrganizationService interface</param>
/// <param name="principal">The user, team, or organization to revoke rights to the shared record.</param>
/// <param name="record">The shared record</param>
static void RevokeShare(
   IOrganizationService service,
   EntityReference principal,
   EntityReference record)
{
   RevokeAccessRequest request = new()
   {
         Revokee = principal,
         Target = record
   };

   service.Execute(request);
}