This is only my seconds attempt and I tried melting it on a piece of bread in the microwave oven and it melted right away.
In my previous attempt, I made cheese that I tried on pizza and it came out un-melted, and roasted. Did yours melt? if not then probably we got the same results.
I thought that since I'm attempting mozzarella for the first time and the problems are usually in either milk or technique, I thought of resolving the milk issue from the beginning and I got myself raw milk and pasteurized it and that actually solved it so I just need to tweak my technique now.
Remember that eventhough the recipe calls for pasteurized milk, it still doesn't mean that it will work. After talking to a local dairy operator, it turns out that each operator uses different temperatures and of course the higher the temperature, the less usefull the milk is for cheese-making. Add to that, homogenizing the milk also affects your results.
I recommend you try raw milk, at least for your first attempts so you can focus on technique only.