IPA: /nɒnˈfʊl.fɪl.mənt/
KK: /nɑnˈfʊlˌfɪlmənt/
The failure to meet a requirement or obligation.
The nonfulfillment of the contract led to legal issues.
Nonfulfillment → It is formed from "non-" (meaning not) and "fulfillment" (from Old English "fullfyllan", meaning to fill completely). The word "nonfulfillment" means the state of not being filled completely or not achieving a goal.
Think of 'not' ('non-') achieving a 'complete filling' ('fulfillment') — that's what nonfulfillment means.