/// <summary>
        /// Ensure that a manager can access a service. Throw an error if they cannot.
        /// </summary>
        /// <param name="managerId">Manager ID</param>
        /// <param name="serviceId">Service ID</param>
        private async Task _EnsureManagerCanAccessService(string managerId, string serviceId)
        {
            // Check that the manager can access the service
            bool managercanAccess = await _database.ManagerCanAccessService(managerId, serviceId);

            // If the manager does not have access, throw an error.
            if (!managercanAccess)
            {
                throw new NoAccessException();
            }
        }