How do I fix my bricks getting into each other when you place them at certain angles?

I have a 4x4 grid building script. Whenever i try to place a block by the side of another block, the block instead just goes into the other block.

I recommend testing this and building with it for a while to understand what I am talking about.

db = true


local tool = script.Parent

local me = game.Players.LocalPlayer
local mouse = me:GetMouse()


tool.Activated:connect(function()
    if db then
        db = false
        print("placed brick")
        local part = game.ReplicatedStorage.Dirt:Clone()
        part.Parent = workspace
        local offsety = 2
        local a = mouse.Hit -- point a
        local x = a.X
        local y = a.Y
        local z = a.Z
        local x = math.floor(x / 4) * 4
        local y = math.floor(y / 4) * 4
        local z = math.floor(z / 4) * 4
        c = CFrame.new(x,y,z) + Vector3.new(2,offsety,2)
        print(c)
        part.CFrame = c
        wait(.2)
        db = true
    end
end)

"Dirt" is a 4x4 part. db is the cooldown for placing blocks

edit: here's a demonstration of what i am talking about https://youtu.be/sGb2sb4mclo

Use mouse.Target to get the position of the object that the mouse is touching. This way, if you touch the Dirt object, you will get that position and you won't have to do the xyz calculations.

-- use variables!
local ReplicatedStorage = game:GetService("ReplicatedStorage")
local dirt = ReplicatedStorage:WaitForChild("Dirt")
local offsetVector = Vector3.new(2, 2, 2)

tool.Activated:Connect(function() -- use Connect instead of connect
	if not db then return end
	db = false
	local mouseTarget = mouse.Target
	if not mouseTarget then return end
	
	local part = dirt:Clone()
	part.CFrame = mouseTarget.CFrame + offsetVector
	part.Parent = workspace -- parent the part last!
	wait(.2)
	db = true
end)

Hope this helps! :)