The kettle is not hot enough

kongnightt  start by measuring the temp of the kettle. It is possible that this is a thermostat issue but it is also possible that this is a heating element issue. Post some good pictures of your popper and let us know if you have already started to asemble some of the parts etc. The more we can see the greater the chance to finding the error. You need a multimeter to check the heating element.

Yes, pictures will always help specially of parts etc. Post those with your question. Use this guide Adding images to an existing question for that.