Any outgoing trade is not seen by the other person, and incoming trades are stuck pending, this may also be related to how colours and tags take almost 10-30 minutes to update, or sometimes stay the way they are
Trading has been a finicky matter for a while in the DTP, so these issues are not new. By the way, are you sure you have a substantial amount of DP on your account? I don’t remember the specific value, but for every trade there is also DP tariff.
I usually have 1-2k or more dp, and I’m level 45 so I don’t see any problem with the basic requirements
I think that is enough DP for the duty requirement, but I guess you could get more DP if that assumption is wrong. Besides that, try reloading the page and open it up at different times (sometimes the Trading System is down or acting weird.
Again, trading with other players is a very finicky matter.