clear session cookies on new login

timebot.py

@@ -62,7 +62,7 @@ class TimeBot:
 
     def _login(self, session: requests.Session):
         """
-        Obtain session cookie.
+        Clear existing session cookies and try new login.
 
         :raises: on status code != 2xx
         """
@@ -74,6 +74,7 @@ class TimeBot:
             "username": self.user,
             "password": self.password,
         }
+        session.cookies.clear_session_cookies()
         request = session.post(self.baseurl + "Account/LogOn", data=login_data)
         request.raise_for_status()