A few months ago whenever we boiled the kettle we could smell an awful fishy smell.
We changed the kettle.
A few weeks later exactly the same thing.
Suspected the water, changed the filter - still the same.
Checked the kettle and plug, the plastic at the top of the live pin was all deformed and melted just like the one in the picture.
The old kettle was in the garage I checked the plug and it was all melted just the same.
The plastic on these plugs, a supposed safety feature is a death trap, the plastic is just not up to the job.
I changed the plug to an older one with solid brass pins - not a problem since.