access database row and edit one line of existing user

ok what i am trying to do to the best of my ability is create a user username and password witch is done perfectly fine

the issue i am having is once the user is registered i want to save there machine id i have the following code to do so

This is my connection string i have assigned the database file address path string connString; connString = $"SERVER={server};DATABASE={database};UID={uid};PASSWORD={password};"; string machineidfull = processorid + mbored; This is my update query in which i am taking input from the user through windows forms and update the record. string Query = "update elfenliedtopfan5_login set users(machineid='" + machineidfull + "');"; This is MySqlConnection here i have created the object and pass my connection string. MySqlConnection MyConn2 = new MySqlConnection(connString); MySqlCommand MyCommand2 = new MySqlCommand(Query, MyConn2); MySqlDataReader MyReader2; MyConn2.Open(); MyReader2 = MyCommand2.ExecuteReader(); MessageBox.Show("Data Updated"); while (MyReader2.Read()) { } MyConn2.Close();Connection closed here

but the issue i have is it gives me the following error

{"You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '(machineid='BFEBFBFF000906E9170808xxxxxxx')' at line 1"}

also i know its unrelated i think to this but is there a way to ban users as well so if the machine id is not listed as a accessed user then it will stop user using my program

thanks in advance elfenliedtopfan5