ON JOHN THE BAPTIST AND ELIJAH

[jeremiah1five]

11 And they asked him, saying, Why say the scribes that Elias must first come? 12 And he answered and told them, Elias verily cometh first, and restoreth all things; and how it is written of the Son of man, that he must suffer many things, and be set at nought. 13 But I say unto you, That Elias is indeed come, and they have done unto him whatsoever they listed, as it is written of him. Mk 9:11–13.

Jesus is speaking of John the Baptist. He also says Elijah is come and He connects John the Baptist to Elijah.
But when John the Baptist is asked whether he is Elijah he denies it.

And they asked him, What then? Art thou Elias? And he saith, I am not. John 1:21.

What's going on here? Who's lying and who's telling the truth?
Is John the Baptist Elijah?

 

[jeremiah1five]

26 views at this time and no one knows the biblical answer.

More disappointment.

 

[Fastfredy0]

26 views at this time and no one knows the biblical answer.

More disappointment.

But I say to you that Elijah has indeed come, and they did to him whatever they wished, just as it is written of him.” (9:13)
Jesus’ definitive statement, “But I say to you that Elijah has indeed come,” must have surprised and puzzled the disciples, leaving them even more confused than they already were. But Elijah had not literally returned; the Lord was referring to the one who came “in the spirit and power of Elijah” (Luke 1:17)—John the Baptist. There were striking similarities between the two prophets, including their physical appearance (cf. 2 Kings 1:8 with Mark 1:6) and their powerful, uncompromising preaching. Yet when the Jewish leaders asked him, “Are you Elijah?” John replied, “I am not” (John 1:21).
Although the disciples now realized that Jesus was referring to John the Baptist (Matt. 17:13), Israel had failed to recognize John’s significance (Matt. 17:12) and did to him whatever they wished, just as it is written of him . The religious leaders rejected him (Matt. 21:25; Luke 7:33), and Herod imprisoned and killed him (Mark 6:17–29)—the fate intended for Elijah (1 Kings 19:1–10). No specific Old Testament prophecies predicted the death of Messiah’s forerunner, so the phrase it is written of him is best understood as having been fulfilled typically by John.
Had Israel realized who John was and accepted his message, he would indeed have been the Elijah who
was to come (Matt. 11:14). But since they did not, John was a preview of another who will come in the spirit and power of Elijah before the second coming (possibly one of the two witnesses; cf. Rev. 11:3–12).
The biblical pattern is clear. Elijah was rejected and persecuted; Messiah’s forerunner, who came in the spirit and power of Elijah, was rejected and killed, and Messiah Himself was rejected and murdered. In the future, however, the prophesied Elijah will come, the Lord Jesus Christ will return, and the kingdom will be established.
John MacArthur

Aside: The seeming conflict in regards to your question has always perplexed me.