If you have only been playing a little while, I’d probably
chalk it up to technique. You can’t be certain though
until you have tried on other harmonicas. This one could
need some tweaking. Have you practiced with your bends
while watching a chromatic tuner? Bend and hold the note
as true as possible for several seconds. On the three hole
for instance, bend 1/2 step and hold. Do this several repetitions.
Now bend a whole step the same way. Do this with all
available bends on all holes. Don’t think that just because
the harp won’t bend, you have a mechanical problem (you
could need to tweak your reeds though). Can you do blow bends,
overblows, etc.? Bends come with practice. When you get
well able with bends, there will hardly be a harp that won’t bend
for you. Some may not bend well and will take some effort,
but then you will know for sure it is not you. Find the harp that’s
easiest for you to bend and stick with that one for a time.
You will be surprised how your embouchure will learn “automatic”
responses, and you will hit the correct bends without thinking
or working at it. It will be fluid.