I will echo the comment here but with a bit of additional opinion.
I buy guns/ammo for sale at work. I ordered a great deal of our years supply during the month of December when most of the wholesaler's hold their buyers shows.
It's now March and I have less than 50 percent of my ammo (bulk) orders.
So, if you ordered something that was "in stock", then you have waited too long already.
If you "pre-ordered" something they were sourcing on a "placing order", that should have been made clear by the vendor with the added information that you may not see it until the third quarter of the year (as a worst case).
Now you say it's just "9mm", but there is some variety there - late last year I could get cases of PMC, as many as I wanted. Currently, most PMC branded stuff is on back-order (just as an example). But my pre-order "fixed the price" at what it was selling for in December, so even though our buck has lost another 3 or 4 cents, it hasn't effected our buying price. And that's my only point. You may just have not got the "full story" of what you were ordering - talk to the vendor and if you can't wait, cancel your order...