diff --git a/internal/api/controller/user/login.go b/internal/api/controller/user/login.go
index 9779fbf6c..bbbcda797 100644
--- a/internal/api/controller/user/login.go
+++ b/internal/api/controller/user/login.go
@@ -23,8 +23,8 @@ import (
 )
 
 type LoginInput struct {
-	Username string `json:"username"`
-	Password string `json:"password"`
+	LoginIdentifier string `json:"login_identifier"`
+	Password        string `json:"password"`
 }
 
 /*
@@ -34,15 +34,15 @@ func (c *Controller) Login(ctx context.Context, session *auth.Session,
 	in *LoginInput) (*types.TokenResponse, error) {
 	// no auth check required, password is used for it.
 
-	user, err := findUserFromUID(ctx, c.principalStore, in.Username)
+	user, err := findUserFromUID(ctx, c.principalStore, in.LoginIdentifier)
 	if errors.Is(err, store.ErrResourceNotFound) {
-		user, err = findUserFromEmail(ctx, c.principalStore, in.Username)
+		user, err = findUserFromEmail(ctx, c.principalStore, in.LoginIdentifier)
 	}
 
 	// always return not found for security reasons.
 	if err != nil {
 		log.Ctx(ctx).Debug().Err(err).
-			Str("user_uid", in.Username).
+			Str("user_uid", in.LoginIdentifier).
 			Msgf("failed to retrieve user during login.")
 		return nil, usererror.ErrNotFound
 	}
diff --git a/internal/api/controller/user/register.go b/internal/api/controller/user/register.go
index 9323a8e82..b5506c72b 100644
--- a/internal/api/controller/user/register.go
+++ b/internal/api/controller/user/register.go
@@ -14,8 +14,8 @@ import (
 
 type RegisterInput struct {
 	Email       string `json:"email"`
-	DisplayName string `json:"displayname"`
-	Username    string `json:"username"`
+	DisplayName string `json:"display_name"`
+	UID         string `json:"uid"`
 	Password    string `json:"password"`
 }
 
@@ -24,10 +24,15 @@ type RegisterInput struct {
  * This differs from the Create method as it doesn't require auth, but has limited
  * functionalities (unable to create admin user for example).
  */
-func (c *Controller) Register(ctx context.Context, in *CreateInput) (*types.TokenResponse, error) {
+func (c *Controller) Register(ctx context.Context, in *RegisterInput) (*types.TokenResponse, error) {
 	// TODO: allow to configure if open register is allowed.
 
-	user, err := c.CreateNoAuth(ctx, in, false)
+	user, err := c.CreateNoAuth(ctx, &CreateInput{
+		UID:         in.UID,
+		Email:       in.Email,
+		DisplayName: in.DisplayName,
+		Password:    in.Password,
+	}, false)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create user: %w", err)
 	}
diff --git a/internal/api/handler/account/register.go b/internal/api/handler/account/register.go
index 4392b047f..2ff1b5faa 100644
--- a/internal/api/handler/account/register.go
+++ b/internal/api/handler/account/register.go
@@ -25,12 +25,7 @@ func HandleRegister(userCtrl *user.Controller) http.HandlerFunc {
 			return
 		}
 
-		tokenResponse, err := userCtrl.Register(ctx, &user.CreateInput{
-			UID:         in.Username,
-			Email:       in.Email,
-			DisplayName: in.DisplayName,
-			Password:    in.Password,
-		})
+		tokenResponse, err := userCtrl.Register(ctx, in)
 		if err != nil {
 			render.TranslatedUserError(w, err)
 			return