Indulgence is a noun that means:
* The act of allowing oneself to enjoy something, especially a pleasure or luxury. For example, "She indulged in a long, hot bath after a stressful day."
* A thing that is enjoyed or allowed as a special treat or privilege. For example, "Chocolate is my guilty indulgence."
* (in the Roman Catholic Church) a remission of temporal punishment due to sin. This is a more historical and religious meaning.
If you were trying to use "endulgement" in a sentence, it is likely that you meant to use "indulgence" instead.