Can anyone help me with this TextLabel / GUI issue?

Okay, I think I got the problem ironed out; the problem here I'm having is that after any ****wait****, you can no longer set the "Text" element in the text label. However, I want to fix this, and I can't seem to find anywhere, or anyone, that has had / written about this issue. If anyone could help, much would be appreciated. The script is provided below.

script.Parent.Parent.StarterGui.Playing.text.Text = "Preparing music, please wait...."
wait(5)
script.Parent.Parent.StarterGui.Playing.text.Text = "Now Playing: Pretty Girls by Brittany Spears ft. Iggy Azalea"
script.Parent.Music_System.Pretty_Girls:Play()
wait(79)
script.Parent.Parent.StarterGui.Playing.text.Text = "Preparing next song, please wait...."
script.Parent.Music_System.Pretty_Girls:Stop()
wait(2)
script.Parent.Parent.StarterGui.Playing.text.Text = "Now Playing: Watch Me (Whip / Nae Nae) by Silento"
script.Parent.Music_System.Watch_Me:Play()
wait(120)
script.Parent.Parent.StarterGui.Playing.text.Text = "Preparing next song, please wait...."
script.Parent.Music_System.Watch_Me:Stop()
wait(2)
script.Parent.Parent.StarterGui.Playing.text.Text = "Now Playing: Sugar by Maroon 5"
script.Parent.Music_System.Sugar:Play()
wait(120)
script.Parent.Parent.StarterGui.Playing.text.Text = "Preparing next song, please wait...."
script.Parent.Music_System.Sugar:Stop()
wait(2)