“There were also false prophets among the people, just as there will be false teachers among you.” (2 Peter 2:1)
There are no “ifs, ands, or buts” in Peter’s words. It’s a clear and definite statement. There were false prophets among the people (of Israel in the Old Testament). That’s a matter of history.
False prophets were a constant problem in the Old Testament, and those who falsely claimed to be prophets of God were to be stoned. The people rarely had the will to deal with them, so they multiplied, causing disaster to the spiritual life of God’s people.