I have many Instant ON switches around and, as already written, are very reliable. Not many were replaced for HW failures.
Check the power cable and connections. Sometimes plug can slip from switch if it is not completely inserted into receptacle.
Try with different power outlet.
If nothing works, just open the case and switch will be replaced,
Limited lifetime warranty is for original owner. It does not apply for second hand switches.
Best, Gorazd
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Gorazd Kikelj
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