Plastic lid seals poorly preventing shutoff

I bought this to replace a 20+ year old Russell Hobbs that finally gave up. The design is nice with a large lid that easily allows filling and cleaning.

However upon use, the flimsy plastic lid does not lock down and when in operation flexes upward. When the water boils, the flexible lid delays shutoff and if the kettle is full (which the instruction recommend for best shutoff operation) boiling water splashes outside the kettle.