2 sliding panels

I have 2 sliding panels. When I click 1 button its panel slides in - disables the other button from allowing the second panel to slide. And if you click the same button again it slides the panel back off screen and re enables the second panel button.
What I would like to do is when I click on a button if the other panel is visible then hide it the show its own panel

        private void btnSent_Click(object sender, EventArgs e)
        {
            if (btnInTransit.Enabled == true)
            {
                btnInTransit.Enabled = false;
            }
            else
            {
                btnInTransit.Enabled = true;
            }
            btnSent.Enabled = false;
            if (PanelLocation == 1)
            {
                panel2.Visible = true;
                //if showing - hide
                for (int i = 0; i < panel2.Width; i++)
                {
                    panel2.Location = new Point(746 + i, panel2.Location.Y);
                }
                PanelLocation = 0;
                panel2.Visible = false;
            }
            else
            {
                //if hidding - show
                panel2.Visible = true;
                for (int i = 0; i < panel2.Width; i++)
                {
                    panel2.Location = new Point(1017 - i, panel2.Location.Y);
                    panel2.Invalidate();
                }
                PanelLocation = 1;
            }
            btnSent.Enabled = true;
        }
        private void btnInTransit_Click(object sender, EventArgs e)
        {
            if (btnSent.Enabled == true)
            {
                btnSent.Enabled = false;
            }
            else
            {
                btnSent.Enabled = true;
            }
            btnInTransit.Enabled = false;
            if (PanelLocation == 1)
            {
                panel1.Visible = true;
                //if showing - hide
                for (int i = 0; i < panel1.Width; i++)
                {
                    panel1.Location = new Point(746 + i, panel1.Location.Y);
                }
                PanelLocation = 0;
                panel1.Visible = false;
            }
            else
            {
                //if hidding - show
                panel1.Visible = true;
                for (int i = 0; i < panel1.Width; i++)
                {
                    panel1.Location = new Point(1017 - i, panel1.Location.Y);
                    panel1.Invalidate();
                }
                PanelLocation = 1;
            }
            btnInTransit.Enabled = true;
        }

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