Thank you for asking your question on Just Answer. This is an indication that your thermocouple is defective. Remove the thermocouple and take it to any hardware or home improvement and they will match the length and provide you with a replacement thermocouple. When you reinstall the thermocouple just male sure the flame on the pilot light is hitting the thermocouple. See the image below. It may not be exactly like yours but it will be similar.
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