We're not able to help you unless you give more details as to what is happening.

Also, have you tried using a different browser or seeing if there is an extension conflict with any addons?

when i want to do a new trade offer the inventory is not working

You need to provide more detail. Are you trying to create a new trade? What are you trying to trade? What for? What's the error message that you get (if there is any)?

I already found a fix for you.
You have a private profile and backpack, TF2Outpost can not fetch your backpack so you can't make a trade, is it really that hard to read rules?
You have 12 hours to make your profile public before I have to close your account, forcing you to either stop using the site or actually applying to our rules

its doesnt work and my steam is public

No it isn't [outpost.gg]

i put him now private

but when it is in public it diesnt wwwork

Yes i have the same problem and my profile is public

Ok it works now ???
Probably a problem with steam i guese

i dont know what to do and nobody help me

Originally posted by Arrow:

i dont know what to do and nobody help me

You have a private profile and backpack, TF2Outpost can not fetch your backpack so you can't make a trade.

Ahem, this was your original answer but now that I see you have changed the privacy settings, is the exact same problem still re-occurring or are you having another, unrelated issue? It is quite hard to diagnose a problem when you have limited information to start with. Perhaps you can take a screenshot what you are seeing on the site?

it is the same problem.
when my steam is public im going to outpost and i do new trade but its stucks on loading my inventory

You haven't answered my questions. What are you trying to trade? If it's a game or a background then most probably your inventory is set to private.

You need to set your Steam Gifts inventory to public as well and it will work. To do so though you need to uncheck the box at the bottom.