Why isn't MySQL recording?

Question

MySQL

I have code:

from mysql.connector import MySQLConnection, Error

class mysqlighter:
    def __init__(self, db_conf):
        self.conn = MySQLConnection(**db_conf)
        self.cursor = self.conn.cursor()
    
    def add_coin(self, coinsID, coins_symbol, coins_name):
        """Добавляем список коинов"""
        with self.conn:
            query = """INSERT INTO coinTables(id,symbol,name)
                VALUES(%s,%s,%s)"""
            args = (coinsID, coins_symbol, coins_name)
            print(self)
            print(self.cursor)
            try:
                self.cursor.execute(query, args)
            except Error as error:
                print(error)
        
    def coin_Tables(self):
        with self.conn:
            self.cursor.execute("DROP TABLE coinTables")
            create_table = """
            CREATE TABLE coinTables (
            id VARCHAR(255) NULL,
            symbol VARCHAR(255) NULL,
            name VARCHAR(255) NULL);
            """
            self.cursor.execute(create_table)

The coin_Tables function works well, but the add_coin function throws an error

2055: Lost connection to MySQL server at 'localhost:3306', system error: 9 Bad file descriptor

What is it and how to fix it?