I have had the thermostat changed and my polit light from my hot water heater is still going out?

The thermocouple is what the flame touches in order to keep the combination valve open. Only the tip of the flame should touch the thermocouple, and if you need to replace it, any hardware store sells them for about $20.00 and takes about 10 min to install.
I have had the thermostat changed and my polit light from my hot water heater is still going out?
change the thermo couple. easy to do.
I have had the thermostat changed and my polit light from my hot water heater is still going out?
should have changed the thermocouple

vb

Duvet cover