Based on the code snippet you provided, there is no code that directly changes the color of any item. The code you provided only disables several controls when the button is clicked. Without further information or additional code, it is not possible to determine why the color of each item is being changed automatically.
There might be a possible solution though (disabling controls might be the issue)-
Default Behavior: It's possible that the controls you are using have a default behavior that changes their color when they are disabled.
Event Handlers: There might be event handlers or style-related code in other parts of your application that are triggered.
External Code: The behavior you are experiencing could be a result of code executed elsewhere in your application or in a separate component or library.
To change the behavior you can try the following -
private void btnStart_Click(object sender, EventArgs e)
this.grSettings.Enabled = false;
this.grTelegramSetting.Enabled = false;
this.grTradeSetting.Enabled = false;
this.grAccountSetting.Enabled = false;
this.btnCreateOrder.Enabled = false;
this.cbCheckBlance.Enabled = false;
this.btnClosePositionTest.Enabled = false;
this.btnStart.Enabled = false;
this.btnStop.Enabled = true;
this.grSettings.BackColor = Color.Red;
this.grTelegramSetting.BackColor = Color.Blue;