I bought sugar free chocolate syrup by accident. Anyway of making it NOT sugar free and not ruining it?

Your sugar free chocolate syrup has an artificial sweetener in it, so adding sugar or corn syrup will make it way too sweet. Of course if the chocolate syrup is unsweetened, which in not something I have ever seen in the market, you could make a sugar syrup with a small amount of water and sugar and mix that with the syrup or you could just add Karo corn syrup.

I don't think so. It's already been made up as it is. Not really much you can do about that. Just go ahead and use it. Or if you just recently bought it and still have the receipt and it's an unopened bottle, then take it back to the store and get a refund or exchange.

Why bother, sugar free is best or just return it to store and exchange it if it bothers you that much

If you didn't open it and happen to have the receipt you can take it back for an exchange.

lion