ANSWER: The quick answer is NO, there is no contradiction of the scriptures. That said, SEVERAL have seen God, the Son. The apparent contradiction is one brought about by a misunderstanding of what is called the Godhead. The easiest route to understanding this sometimes difficult to comprehend subject is to review the scriptures below.
"In the beginning was the Word, and the Word was with God, and the Word was God." (John 1:1 - 3)
As the context shows, John is speaking of Jesus who was with the Father at the beginning and who, Himself, WAS God.
Moses asked God to tell him His name so that he could tell the enslaved Israelites in Egypt who it was that sent him to them. The answer to his request was the following.
14 God said, 'I am who I am. You must tell them: 'The one who is called I AM has sent me to you.' (Exodus 3:14)
Later, when Jesus was on this earth living as a man, He told those He was speaking directly to that He was, indeed, the "I AM." Jesus, speaking to the religious leaders of Israel who thought highly of themselves because they had Abraham as their father, told them that "before Abraham was born, I AM!" (John 8:58).
Why did they fall BACKWARDS?
Let me digress a moment from answering your question to offer something to consider. John 18 contains the record of Jesus being arrested in the Garden of Gethsemane. A group of religious leaders, troops, and others, led by Judas, come to the Garden to arrest Christ. Upon their arrival they are asked whom they are looking for (John 18:4). They respond they are looking for Jesus. Christ's answer and what happens next, overlooked by many, is rather dramatic and revealing.
Jesus said to them, "I AM" . . . 6. But when He said to them, "I AM," they went backward and fell to the ground. (John 18:5 - 6, HBFV)
In the KJV and other Bibles, the word "he" is added to the phrase "I AM" in an attempt by the translators to make the passage more understandable. However, it does just the opposite! I believe such an addition OBSCURES the fact that when Jesus said "I AM" His speaking of His own name was so powerful it knocked the soldiers to the ground!! How else can this passage be explained?
How many Beings are there?
From the scriptures mentioned at the beginning of this answer and from many others we learn that the doctrine of monotheism (the belief there is literally only ONE Being in the Godhead) normally associated with Judaism and the vast majority of Christianity is FLAWED. There are TWO beings Who are God: the Father and the Son. While it is true that the Godhead is "one" (Deuteronomy 6:4), the Hebrew word translated as "one" is echad, which is the same Hebrew word translated as "one" in Genesis 2:24, saying that a man and his wife shall become "one" flesh.
Jesus was born and lived on this earth as a man, prayed to and obeyed the will the Father. Jesus was cruelly murdered, resurrected, returned to His former station and was given all authority in heaven and the earth. (Matthew 28:18, John 8)
The Bible clearly tells us, in several places, that NO ONE has ever seen the Being of the Godhead known as the Father (Exodus 33:19 - 20, John 1:17 - 18, 5:37, 6:46, 1John 4:12, 1Timothy 6:15 - 16, etc.). Several people in the Bible DID see a pre-incarnate Jesus Christ such as Jacob (Genesis 32:24 - 38) and Job (Job 42:1, 5). And, of course, many people saw Jesus or God the Son during his ministry on earth (1John 4:14).