Re. Amos 3:7 This verse is saying that God will not contradict what the prophets have already prophesied in the Bible, not that God must always have a prophet on earth. Always read more than what a “prophet” tells you to read.
Hebrews 1:1-2 In the past God spoke to our forefathers through the prophets at many times and in various ways, but in these last days he has spoken to us by his Son, whom he appointed heir of all things, and through whom he made the universe.
I John 4:1 Dear friends, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world.
Matthew 7:15-16 “Watch out for false prophets. They come to you in sheep’s clothing, but inwardly they are ferocious wolves. By their fruit you will recognize them. Do people pick grapes from thornbushes, or figs from thistles?
Your interpretation of Amos 3:7
I find to be a gross mangling of the text.
The text clearly does NOT say what you assert.
You are welcome to assert your biases about such things. However, that verse does NOT support your biases.