diff --git a/backend/routes/member/create_member.go b/backend/routes/member/create_member.go
index 4b59b1e..824735e 100644
--- a/backend/routes/member/create_member.go
+++ b/backend/routes/member/create_member.go
@@ -65,15 +65,15 @@ func (s *Server) createMember(w http.ResponseWriter, r *http.Request) (err error
 	}
 
 	if err := validateSlicePtr("name", &cmr.Names); err != nil {
-		return err
+		return *err
 	}
 
 	if err := validateSlicePtr("pronoun", &cmr.Pronouns); err != nil {
-		return err
+		return *err
 	}
 
 	if err := validateSlicePtr("field", &cmr.Fields); err != nil {
-		return err
+		return *err
 	}
 
 	tx, err := s.DB.Begin(ctx)
@@ -175,7 +175,7 @@ func validateSlicePtr[T validator](typ string, slice *[]T) *server.APIError {
 		if s := pronouns.Validate(); s != "" {
 			return &server.APIError{
 				Code:    server.ErrBadRequest,
-				Details: fmt.Sprintf("%s %d: %s", typ, i, s),
+				Details: fmt.Sprintf("%s %d: %s", typ, i+1, s),
 			}
 		}
 	}
diff --git a/backend/routes/member/patch_member.go b/backend/routes/member/patch_member.go
index b909a5b..dd5077e 100644
--- a/backend/routes/member/patch_member.go
+++ b/backend/routes/member/patch_member.go
@@ -115,15 +115,15 @@ func (s *Server) patchMember(w http.ResponseWriter, r *http.Request) error {
 	}
 
 	if err := validateSlicePtr("name", req.Names); err != nil {
-		return err
+		return *err
 	}
 
 	if err := validateSlicePtr("pronoun", req.Pronouns); err != nil {
-		return err
+		return *err
 	}
 
 	if err := validateSlicePtr("field", req.Fields); err != nil {
-		return err
+		return *err
 	}
 
 	// update avatar
diff --git a/backend/routes/user/patch_user.go b/backend/routes/user/patch_user.go
index a54b68b..486fc7f 100644
--- a/backend/routes/user/patch_user.go
+++ b/backend/routes/user/patch_user.go
@@ -89,15 +89,15 @@ func (s *Server) patchUser(w http.ResponseWriter, r *http.Request) error {
 	}
 
 	if err := validateSlicePtr("name", req.Names); err != nil {
-		return err
+		return *err
 	}
 
 	if err := validateSlicePtr("pronoun", req.Pronouns); err != nil {
-		return err
+		return *err
 	}
 
 	if err := validateSlicePtr("field", req.Fields); err != nil {
-		return err
+		return *err
 	}
 
 	// update avatar
@@ -250,7 +250,7 @@ func validateSlicePtr[T validator](typ string, slice *[]T) *server.APIError {
 		if s := pronouns.Validate(); s != "" {
 			return &server.APIError{
 				Code:    server.ErrBadRequest,
-				Details: fmt.Sprintf("%s %d: %s", typ, i, s),
+				Details: fmt.Sprintf("%s %d: %s", typ, i+1, s),
 			}
 		}
 	}