The F11 error means there is a drainage issue.
Please, do the following:
- check the drain hose outlet for foreign objects and clogs.
- make sure the drain hose is not kinked.
- check the drain pump for blockages and clean it if necessary.
When you have done the above, drain the machine by launching a drain cycle or press the door opening button (look for the key symbol). If this does not work, contact your local service center.