public static void PutUserRegister(UserDetails newUserDetails, PostNewRegisterCallback callback) { DBCommunicator.GetLastUserID(uID => { uID.LastUserID += 3; DBCommunicator.PostLastUserID(uID, () => { }); newUserDetails.uId = uID.LastUserID; RestClient.Put <UserDetails>($"{databaseURL}Users/{newUserDetails.uId}.json", newUserDetails).Then(response => { callback(newUserDetails.uId); }); }); }