Turn your suitcase upside down. At this position all your numbers look upside down. Now with the help of a torch light you should see a small gap above the rotating thing (the one with which you change your number) Take the first rotating thing and rotate from 0 to 9, at some particular number you can see a small hole inside the small gap which I have mentioned before. Do the same for the next 2 rotating thing.
When you are done you can see the small hole(a tiny spring like material is seen in the hole) in all the three small gaps.
Now you can open the number lock.