As below, a poor connection on the plug lead could very well be the issue in addition to a failing heater element. Taking into account the potential safety issues of a faulty appliance, a Morphy Richards kettle is simply not worth wasting the time or effort trying to perform a repair. They are so cheap that I'd advise chucking it in the bin and buying a £15 new one from Argos in the morning.
Check the plug, lead and socket are not getting hot. Replace if necessary
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