Scam Through Facebook Marketplace

Hi, this is Sahdin Khan from Dhaka. I was looking for a musical keyboard for my sons. On 30th June i came across few musical instruments from the same seller with a lower price. Tha ads declared the product were sezied from Benapole Customs and they took it on Tender to sell it in a certain time frame (Now all the ads have been removed). I have taken screenshots of them. I contacted them and asked them about the product and low price also. They said the price was determined by BD Customs which they have no control over. They are actually just C&F agent. Thinking it was a good deal as the product was new instead of used i was looking for i went forward with it. It was 35000tk. I initially paid 10500 tk as booking money as their tender was ending on 30th june 6.30pm which was mentioned on the ad. Next morning 1st July they contacted me and sent me a SA Paribahan Courier receipt and asked for the remaining 25000tk. Which i sent. Unfortunately i didn’t see they were covering the Serial Number on the receipt. On top of that I thought any receipt could be traced through our Ph Numbers. So Insent the money and they said they sent the Product. All NAGAD transactions. I requested them to send me the Courier receipt with the serial number and they stopped communicating with me. I sent them hundreds of msgs and called hundreds of time. They kept saying we are sending the receipt in 1/2 hours. But it never came. Neither did the Product. I went to SA Paribahan. I was Surprised to know in this day and age they couldn’t track anything with Mobile numbers. They needed the Receipt Serial number which was covered in the picture i was sent. So ket kept calling for next 3 days. They got angry with me for bothering them. So now i paid full amount, didn’t get the product and not even have a proof that they sent it. Only positive thing the phone number is still active even though nobody is receiving it. I am posting all the ads, my conversations with them and transaction details. 

The Name and number given to Me was Rezaul Karim,01783202299. Shopno Traders. 

If anybody can please help.