If the lid of the Mixing Bowl is not keeping liquids in the bowl while mixing food, it is important to make sure the lid is properly seated on the top of the bowl. Sometimes it is helpful to push the lid down with 2 or more fingers from both hands and even twist the lid a little on top of the bowl, as it is pushed down. If the lid continues to leak, the lid should be replaced. The Thermomix® and the locking mechanism is not in need of repair.
If you need further assistance, please contact us at https://service.thermomix.com/hc/en-us/requests/new. Our Customer Happiness agents will get back to you in 1-2 business days.