Charles Ellicott Commentary 2 Kings 1:5

"And the messengers returned unto him, and he said unto them, Why is it that ye are returned?" — 2 Kings 1:5 (ASV)

Turned back to him. —To Ahaziah, as the Syriac and Vulgate actually read. Literally, And the messengers returned unto him, and he said, etc. Though Elijah was unknown to the envoys, such a menacing interposition would certainly be regarded as a Divine warning, which it was perilous to disregard.

Why are you now turned back? — Why have ye returned? with emphasis on the "Why."