cheating with trading

Today I decided to buy the oldest saronite, in the chat I was looking for a player who had 20 pieces, the offer was 500 gold per unit, we have the character Screwley, we make a deal, I look at 20 units in the trade window, enter the amount of 10,000 gold and press trade, the result is 1 unit ancient saranite and the player just immediately leaves the network, the deal was quick, so this player was preparing in advance for this step of deception, please punish according to server rules. Trust in the local server community, well it just doesn’t exist anymore. The only evidence is a screenshot of the correspondence.