When cleaning the closure to the underside of the lid solves this by locking mechanism and can not be reattached. The manufacturer suggests easy cleaning but this very critical area in which slightly disgusting "muck" settles is very difficult to reach. Substituting doing a little too much pressure, in order, for example, with a Schwämchen to remove the deposits between the locking mechanism and the lid, this is broken.
Too bad the otherwise this would be the perfect thermo.
Also do not understand why I can return the product for one month only.