So i made trade where i was selling fists of steel strange part: long distance kills and tanks destroyed and carl hat But then i accidentally but the price to only 1 ref and now i have lost like 4 ref... Is it possible to get them back??

Man, that sucks, but from the FAQ (http://dispenser.tf/s/faq/):

3. Would you compensate for my loss if I lose my items or credit?

We compensate for loss that is caused by our errors. Normally, an item will not disappear itself for no good reason. There could be glitches and bugs, causing items to be occasionally not showing up in your inventory or credits not being calculated properly. But they will not cause you any actual loss. You can report all these problems to us on our forum and we will fix them for you as soon as possible.
We do not compensate for any loss that is caused by your misunderstanding of features: setting up trades with an inappropriate trade type or choosing items you do not want in wishlist, etc. Please read FAQ Part 2 to be more familiar with trade types and wishlist. For all 'lost items' that we have picked up from our bots, we will keep only up to 300 of them. When our limit is reached, we will be removing some of those items to free up space.