How do i make this script make a random selection but (different) random selection?

I dont want the song to be the same one right after it plays once in a row. how do i fix?

local songValues = {}
local songs = script.Parent:GetChildren()

for i,v in pairs(songs) do
	if v:IsA("IntValue") and v.Name == "MusicId" then
		table.insert(songValues, v.Value)
	end
end

local sound = Instance.new("Sound",script.Parent)
sound.Name = "MusicPlayer"
	

sound.Pitch = pitch
sound.Volume = volume

while true do
	sound.SoundId = "rbxassetid://"..songValues[math.random(1,#songValues)]
	sound:Play()
	wait(songPlayTime)
	sound:Stop()
	wait(nextSongPlayTime)
end

First approach

Well first, I recommend you create a pseudo table you can use to control what random values you can access, and eliminate the already chosen ones.

Second approach

Next, I'll just be optimizing some minor details that aren't really relevant in this situation, but it certainly doesn't hurt. I'll go over most of it in commented text.

-- Creating a reference to the script's parent (because why not)
local SongHolder = script.Parent

-- The array that will contain all the song Ids
local Songs = {}

-- Get the IntValues from the script's parent and assort it appropriately to the array. Here I'm using a numeric for loop, just because I find it easier to identify with when iterating an array.
for i = 1,#SongHolder:GetChildren() do
	local v = SongHolder[i]
	if v:IsA("IntValue") and v.Name == "MusicId" then
		Songs[i] = v.Value -- Insert the value to the Songs list
	end
end

Now for the part you're looking for, the random selection loop. Here we'll use a while loop, that will continuously run a numeric for loop with different values to choose from each time. Here's an example:

local SoundPlayer
local SongHolder = script.Parent
local Songs = {}

for i = 1,#SongHolder:GetChildren() do
	local v = SongHolder[i]
	if v:IsA("IntValue") and v.Name == "MusicId" then
		Songs[i] = v.Value 
	end
end

-- Create the sound instance
SoundPlayer = Instance.new("Sound",SongHolder)

-- Main loop
while true do

	-- The new table we'll use to manipulate random values from
	local selection = {}

	-- Basically clone the "Songs" table to the "selection" table
	for i = 1,#Songs do
		selection[i] = Songs[i]
	end

	-- Now comes the main for loop that will do the actually selecting of the random songs
	for i = 1,#selection do
		
		-- Acquire our random index
		local rand = math.random(#selection)

		-- Remove the value from what we can choose from again, while setting the SoundPlayer's sound Id to the value (since table.remove returns the value you're removing)
		SoundPlayer.SoundId = "rbxassetid://"..tostring(table.remove(selection,rand))

		-- Play the sound
		SoundPlayer:Play()

		-- Don't move to the next random song until the current one has finished playing.
		SoundPlayer.Ended:wait()

	-- End the main for loop
	end

-- End the main while loop
end

Summary

So basically all we're doing is creating another table that holds the same references as our initial "Songs" table, and removing the random values we choose as we go down the numeric for loop, to prevent choosing the same random value again.

Questions

Hope this helped, let me know if you have any questions.