Unhappy customer

I have ordered sneakers through a shop named Dressinn which falls under tradeinn in late March and have been waiting for this order since then the last update on the Aftership app was done on the14th April and everytime I try to get answers from them they say the parcel is in customs and they have no control over that, I also went down to post office and they told me that the parcel is not with them yet it might be at the airport, so I am in desperate need of help to know exactly when will my parcel be cleared from customs and be delivered to me because it has been long I am going for 5th month now of waiting. Please assist me in any way you can I have run out of options and do not know how much longer am i supposed to wait.I have called the customs department on so many occasions and all they have to say to me is that they have a backlog and that is totally unacceptable because we have people out there who are still waiting for their parcels from last year so now to me it is like it is easy for them to always hide behind this backlog when you call that is the only excuse they give, they told me that the parcel is still at the airport and I ask them who is responsible to make sure that parcels move and get cleared on time she failed to answer me and hanged up the phone on my ears when I tried calling back she ignored my calls thereafter. So this clearly shows that no one wants to account and people go to work every day but no work is being done clearly hence the backlog because by now they should have worked extra hard to see to it that containers are being attended to and people receive their parcels. Last month In June I did call the customs office again and the lady that I spoke to told me that they do not have the backlog anymore that this is wrong because the people that I have been talking to should have told me that on their system it shows that in May the consignment did arrive but there was no parcel in it and that I should go back to the Dressinn people to ask them what happened to my parcel and I did go back to them and they said to me they are conducting an investigation but in all honesty the wait is too long I have been patient enough with them and I can't anymore I need my refund or the sneakers this month I can no longer wait. Because when reading the Dressinn reviews it goes to show that there are a lot of unhappy customers and they are not doing enough to see to it that people get their parcels as agreed because it's easy for them to take money from the account but when it comes to seeing to it that we receive our parcels they say they can not assist us. I paid a lot of money that I had to make sacrifices for so from March until now its a very long time for one to wait for a parcel. Please assist me in getting my parcel or my refund. My tracking number is RU***NL