The oven went into a lock mode (I suspect this is the child lock?).
There is an key icon in the bottom left corner of display and the oven refuses to turn on.
I’ve searched in the user manual but there is nothing at all about the lock and the key icon is not even mentioned in the user guide.
Yup, I looked pretty much everywhere but couldn’t find a thing on this.
At the end just followed advice by Roy from IT Crowds – turned it off and on again (at the main electrical switch board).
The oven is now working fine 🙂