I found a masterlock glo combination lock in my diy stock clearance bin (no combination code card

I tried the standard masterlock combination method (finding 12 sticking points, 5 prime numbers, the third number is not a number ending in the same number)..
I tried that but didn't work.
I found other opinions suggesting masterlock had recently (or was planning to) change their algorhythm for combination codes.
Does anyone know if this has happened or if I must have done something wrong in working out the combination code....
Thanks,
Brian.