public ResponseModel <string> GetById(string token) { var resp = new ResponseModel <string>(); try { var groupInvite = GroupInvitationsRepository.GetByToken(token); if (groupInvite != null) { var user = UserRepository.GetUserByEmail(groupInvite.Email); if (user == null) { throw new Exception("User not exist"); } var model = new UserGroup() { IdUser = user.Id, IdGroup = groupInvite.GroupId }; if (UserGroupRepository.Exist(model.IdUser, model.IdGroup)) { throw new Exception("User already exist in the group"); } if (UserGroupRepository.Insert(model)) { resp.Data = model.Id.ToString(); resp.Status = 200; resp.Description = "OK"; } else { throw new Exception("Not inserted"); } resp.Data = "OK"; resp.Status = 200; resp.Description = "OK"; } else { resp.Status = 200; resp.Data = null; resp.Description = "GroupInvitations not found"; } } catch (Exception ex) { resp.Status = 500; resp.Description = $"Error: {ex.Message}"; resp.Data = null; } return(resp); }