I am a Thai lawyer. Sent you a message privately.

Sorry for your experience. I am a lawyer. You didn’t give him as a gift but for your business. If you gave him the money in order to do something for you and he didn’t comply and refused to pay you back several time it may be considering guilty of embezzlement which is a criminal case, this is not a civil case. This case is a compromising offense. Please report this to the police so they can take legal action against him. He may be trying to get money to pay you back because he doesn't want to go to jail. Once you receive your money back, you may withdraw your report to the police.

According to the Criminal Code, Section 352 states that anyone who possesses another person's property or owned by others as well fraudulently misappropriating property that belongs to oneself or a third party That person commits an offense of embezzlement. Must be punished with imprisonment not exceeding 3 years or a fine not exceeding 60,000 baht, or both.