diff --git a/src/internal/server/server.go b/src/internal/server/server.go
index 7b31e92..d792e74 100644
--- a/src/internal/server/server.go
+++ b/src/internal/server/server.go
@@ -90,7 +90,7 @@ func (s *Server) GetCache() *redis.Client {
 	return (s.handlers["cache"]).(*redis.Client)
 }
 
-func (s *Server) GetDatabase() *pgxpool.Pool { // FIXME hardcoded index issue
+func (s *Server) GetDatabase() *pgxpool.Pool {
 	return (s.handlers["database"]).(*pgxpool.Pool)
 }
 
diff --git a/src/internal/service/auth.go b/src/internal/service/auth.go
index d56e111..0862a54 100644
--- a/src/internal/service/auth.go
+++ b/src/internal/service/auth.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 
+	db "git.ego.freeddns.org/egommerce/identity-service/pkg/database"
 	"github.com/jackc/pgx/v5/pgxpool"
 )
 
@@ -44,6 +45,9 @@ func (a *Auth) Register(email, login, passwd string) (string, error) {
 	sql := `INSERT INTO identity.users(email, username, password) VALUES($1, $2, $3) LIMIT 1 RETURNING id`
 	err := a.db.QueryRow(context.Background(), sql, email, login, passwd).Scan(&id)
 	if err != nil {
+		if err = db.IsDuplicatedRow(err); err != nil {
+			return "", errors.New("username/email is already taken")
+		}
 		return "", errors.New("Failed to create new user: " + err.Error())
 	}
 
diff --git a/src/pkg/database/connect.go b/src/pkg/database/connect.go
index e8c889c..1e64d92 100644
--- a/src/pkg/database/connect.go
+++ b/src/pkg/database/connect.go
@@ -2,7 +2,9 @@ package database
 
 import (
 	"context"
+	"errors"
 
+	"github.com/jackc/pgx/v5/pgconn"
 	"github.com/jackc/pgx/v5/pgxpool"
 )
 
@@ -14,3 +16,13 @@ func Connect(connStr string) (*pgxpool.Pool, error) {
 
 	return pool, nil
 }
+
+func IsDuplicatedRow(err error) error {
+	var pgErr *pgconn.PgError
+
+	if errors.As(err, &pgErr) && pgErr.Code == "23505" {
+		return errors.New("duplicated row found")
+	}
+
+	return nil
+}