Healing NPC (Heal Code)

Hi there, I would like to make it so even if a person buys health they may not go over the health limit of 100.

function BuyHealth25(ply) 
	if not ply:CanAfford(50) then
		Notify(ply, 1, 4, string.format(LANGUAGE.cant_afford, "25 health"))
		return ""
	if ply.StartHealth and ply:Health() >= ply.StartHealth then
		Notify(ply, 1, 4, string.format(LANGUAGE.unable, "buy 25 health", ""))
		return ""
	ply.StartHealth = ply.StartHealth or 100
	Notify(ply, 0, 4,  string.format(LANGUAGE.you_bought_x, "health",  CUR .. tostring(50)))
	ply:SetHealth(ply:Health() + 25)
concommand.Add("buy_health25", BuyHealth25)

This code makes it so it adds 25 hp to your current health I would like it so if its 99 hp and you buy 25 hp it wont go to 124hp.

Close wrong section.