[SOLVED] Can't buy weapons

Hey Guys,
Yesterday i got a lbig problem.
Last week i got 1st prestige. When i reached lvl 18 i wanted to buy AK-74u.
I normally bought it, but when i went back to Create-Class menu there was still the weapon i had there before a purchase... and money were missing. I DO NOT press escape when it's loading etc. Just can't buy them - Does anyone knows how to fix it or what to do with it?
Thanks for all replies and tips!

reinstall the game
solves most problems

^Not this problem. The problem is steam not syncing properly, causing you to lose some stuff. Nothing you can do at this point. Ive heard of ways to work the game into working, but I dont know what they would be.

How can it be next week? If its not even next week yet?

try only buying the weapon no attachment , no perk
this works for me and im 3 prestige works for me most of time

its just steam cloud,
once exiting the game it syncs all your files, and stats, so just go back into the game play some servers and unlock the new guns.

i had this sht too at lvl 18 1st prestige. but i didnt lost my money.. but when i tryed to buy flamethrower attachment i lost my money and i didnt get it :S but stil works now.