it's a known "issue" with the SegWit wallet in Ledger... it's just asking you to confirm the change address output as well as your actual send output... apparently an update to BTC app 1.1.9 on your ledger should fix this (use Ledger Manager Chrome app to update tr ledger).

see the responses of "btchip" on reddit (they're the Ledger CTO):

https://www.reddit.com/r/ledgerwallet/comments/6yn99h/ledger_nano_s_output2/
https://www.reddit.com/r/ledgerwallet/comments/6wws8e/comfirm_output_2/dmbd7pw/
https://www.reddit.com/r/ledgerwallet/comments/6x4jjc/bitcoin_multiple_output_transaction/