On the assumption that you get a reasonable degree of heat (above say 100c) then a faulty PTC is the likely suspect. What is the full model number suffix ?
ChrisR wrote:User says it gets hot but doesn’t reach temperature.
As you’re probably are aware, elements can heat to a point then go open circuit so you cannot rule out the element being faulty. Thinking about it, a PTC being faulty would more likely cause overheating rather than underheating. So the options are: faulty element, TOC or connections.