example_bot_2.py

import telebot
import sqlite3
import time

# DATABASE CONFIGURATION
conn = sqlite3.connect('sacs_db.db', check_same_thread=False)
cursor = conn.cursor()

def db_wallet(user_id: int, wallet_a: str):
    cursor.execute('INSERT INTO user_db (user_id, wallet) VALUES (?, ?)',
                   (user_id, wallet_a))
    conn.commit()
#---------------------------#

TOKEN = "YOUR_TOKEN"

bot = telebot.TeleBot(TOKEN)

@bot.message_handler(commands=['start'])
def start(message):
    user = message.chat.id
    name = message.chat.first_name

    try:
        cursor.execute(f"SELECT * from user_db WHERE user_id = {user}")
        records = cursor.fetchone()
        data_id = records[0]
        wallet_in_db = records[2]
        bot.send_message(message.chat.id, f"Hello {name}, welcome back!")
    except Exception as e:
        print(e)
        try:
            db_wallet(user_id=user, wallet_a=None)
            bot.send_message(message.chat.id, f"Hello {name}, welcome New user!")
        except Exception as e:
            print(e)



@bot.message_handler(commands=['wallet'])
def start(message):
    user = message.chat.id
    name = message.chat.first_name

    if message.chat.type == 'private':
        try:
            cursor.execute(f"SELECT * from user_db WHERE user_id = {user}")
            records = cursor.fetchone()
            data_id = records[0]
            wallet_in_db = records[2]
            if wallet_in_db == None:
                bot.send_message(message.chat.id, f"Sorry! you didn't set any wallet :/")
            else:
                bot.send_message(message.chat.id, f"Your Wallet is : {wallet_in_db}")

        except:
            bot.send_message(message.chat.id, f"Error! seems you're not in our database")

@bot.message_handler(commands=['set_wallet'])
def start(message):

    sent = bot.reply_to(message, f"Please send your Wallet Adress: ")
    bot.register_next_step_handler(sent, receive)

def receive(message):
    wallet = message.text
    user = message.chat.id
    name = message.chat.first_name
    try:
        cursor.execute(f"SELECT * from user_db WHERE user_id = {user}")
        records = cursor.fetchone()
        data_id = records[0]
        wallet_in_db = records[2]
        print(wallet_in_db)
        db_wallet(user_id=user, wallet_a=wallet)
        bot.send_message(message.chat.id, f"Wallet Updated !")
    except Exception as e:
        print(e)
        db_wallet(user_id=user, wallet_a=wallet)
        bot.send_message(message.chat.id, f"New Wallet Adress added")



while True:
    try:
        bot.polling(none_stop=True)
    except Exception:
        time.sleep(60)

sacs_db.db

CREATE TABLE user_db (
    id              PRIMARY KEY
                    UNIQUE,
    user_id INTEGER UNIQUE ON CONFLICT REPLACE,
    wallet  INTEGER UNIQUE
);