Michael Chare pretended :

Have others had similar problems with this type of kettle?

I bought a cheapy entire glass one, with a flat internal base on ebay,
it lasted a week before element packed in and replaced it with a
similar styled glass one from Lidl - one of the well known names
(Swan/MR ?). Likely a three year guarantee. That has been absolutely
fine so far.

Modern kettles are so cheap these days, they are just not worth
repairing, so why make the elements replaceable? If it breaks in
guarantee, get them to replace it, if outside just buy new. Getting the
replacement part would cost almost as much then there is the fitting
cost of your time.