You loaned a good friend $4,000 in June of last year and they have since refused to pay, which deteriorated the friendship. Yesterday, you beg them to just give you $2,000 and forget about the rest, because you're having a financial emergency. Your friend says they only have $1,700 in their account, and can only give you $1,500. You feel like you have no option but to accept. You give them your account details of a second bank account you have so that they can transfer the money directly to you, which they agree to do the next day.
You wake up and check your bank account and there's $15,000 in it!! You keep staring at the screen, but it is indeed $15K. You grab your phone and immediately see 36 missed calls and 20 texts from your friend. They are begging you to transfer back $13,500. What would you do?