diff --git a/src/crud/authentication.py b/src/crud/authentication.py
index def202a..0f7a9cf 100644
--- a/src/crud/authentication.py
+++ b/src/crud/authentication.py
@@ -16,13 +16,13 @@ ALGORITHM = "HS256"
 ACCESS_TOKEN_EXPIRE_MINUTES = 44640  # One month
 
 
-def authenticate_user(db: Session, user: UserCreate):
+def authenticate_user(db: Session, username: str, password: str):
     """Checks whether the provided credentials match with an existing User"""
-    db_user = get_user_by_username(db=db, username=user.username)
+    db_user = get_user_by_username(db, username)
     if not db_user:
         return False
     hashed_password = db_user.hashed_password
-    if not hashed_password or not pwd_context.verify(user.password, hashed_password):
+    if not hashed_password or not pwd_context.verify(password, hashed_password):
         return False
     return db_user
 
@@ -36,11 +36,11 @@ def register(db: Session, username: str, password: str):
     db.add(db_user)
     db.commit()
     db.refresh(db_user)
-    return db_user
+    return login(db, username, password)
 
 
-def login(db: Session, user: UserCreate):
-    user = authenticate_user(db, user)
+def login(db: Session, username: str, password: str):
+    user = authenticate_user(db, username, password)
     if not user:
         raise HTTPException(status_code=401, detail="Invalid username or password")
     access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
diff --git a/src/main.py b/src/main.py
index b11540c..fb0855d 100644
--- a/src/main.py
+++ b/src/main.py
@@ -66,14 +66,14 @@ async def patch_current_user(
     crud_users.patch_user(db, current_user_name, user)
 
 
-@app.post("/register", response_model=users.User)
+@app.post("/register")
 async def register(user: users.UserCreate, db: Session = Depends(get_db)):
     return crud_authentication.register(db, user.username, user.password)
 
 
 @app.post("/login")
 async def login(user: users.UserCreate, db: Session = Depends(get_db)):
-    return crud_authentication.login(db, user)
+    return crud_authentication.login(db, user.username, user.password)
 
 
 @app.get("/highscores", response_model=List[users.UserHighScore])