Request to refund the wrong currency stash tab to gold coins

My friend suggested that I use gold coins to buy the currency stash tab. After I bought one, I went offline a few hours later and when I went online again, I forgot that I had already bought the currency stash tab. So, I bought another currency stash tab. I don't need two currency stash tabs, and now I don't have enough gold coins to buy other stash tab I need. Please help me refund the wrong currency warehouse page to gold coins. My username is lgk#7467. Thank you.