Cycle of sending sqlite3 database users a message to everyone except telebot?

Question

Bots

What is the question ...
Before that, I wrote code with entering user ids via set (), but now I changed it so that all users are added to the list of the sqlite3 table. I
didn’t change the code much, I just added the code to sqlite3:

def selectuser(self, chat_id):
        with self.connection:
            return self.cursor.execute("SELECT * FROM `userchat` WHERE `chat_id` = ?", (chat_id,)).fetchall()

And in the main block I added only a function call:

userchat = db.selectuser(message.from_user.id)
for user in users:
            if user != message.from_user.id:
                bot.send_message(user, message.text)

For the test I added to the code...
print(message)

... to see if a message was sent

. Only the cycle of sending a message to all people except themselves does not work ( Other people should also be able to send a message to others, except themselves, and when sent correctly, they should receive a message, for example ...

bot.send_message(message.from_user.id, "Сообщение отправлено!")

... by the way, it works, but there is no sending a message from a person to others)

And also, when checking the operation of the code, an error pops up:

2022-03-12 13:23:04,139 (__init__.py:688 MainThread) ERROR - TeleBot: "A request to the Telegram API was unsuccessful. Error code: 400. Description: Bad Request: chat not found"

How can I fix the code to make it work? How to avoid mistakes?