reconfirmation

noun

act of attestation to the truth of, again
requirement that the traveller must notify to the airline that they intend to use their reservation

Wiktionary

noun

Etymology: Etymology tree Proto-Italic *wre- Latin re-der. Old French re-bor. Middle English re- English re- English confirmation English reconfirmation From re- + confirmation.

The act of reconfirming; a second or subsequent confirmation.