In addition, if you sign a one-year contract, the probation period will not exceed two months. If the six-month probation period has expired, the employer shall pay you the salary after the four-month probation period expires. See Articles 19 and 83 of the Labor Contract Law for details.
Personally, I suggest you go to the employer for a labor contract, hand in the 700 yuan, and ask the employer to give you a receipt (with a financial seal) and ask the employer to issue a certificate to terminate the labor contract. If the labor contract has a six-month probation period as you said, and it is a one-year labor contract, you can ask for salary after the four-month probation period expires.