He said I had to make an offer on a specific advertisment by an user and that I had to copy paste a name and a number given by him, that this person was his friend and he will inmediately know what to do, I did as he said.
They have a chat box. Did he ask to send those info in the chatbox.
Not even 3 minutes passed and i realized that the counterpart deposited the money to the number I gave to him, suddenly I understood that I gave a bank account of a third party in the chatbox, however i never specified that the funds had to be transfered there.
I don't understand this part. You said he deposited the money to your number/bank whatever which means he owe the crypto to you. Then why would you even need the customer support?