Remove all controls in a flowlayoutpanel in C#

I'm building a flow layout panel whose each control represents for a room. I want to reload all room by removing all controls in the panel and adding new controls.

I used:

foreach(Control control in flowLayoutPanel.Controls) 
{
    flowLayoutPanel.Controls.Remove(control);
    control.Dispose(); 
}

but some of controls couldn't be removed.

I tried to find a solution on the internet but found nowhere.

Could any body help?