After leaving the property management company, the property management company said that I didn't apply for resignation. What should I do?

According to the information of official website, it is ok to resign orally without writing a resignation application, but it must be approved by the company's personnel department. However, if you leave from some big companies, you may need to complete all the resignation procedures before you can leave safely, otherwise your salary will be deducted. But I suggest you write a resignation application, which is safer and more secure. For details, you can inquire/consult the local authorities to obtain first-hand information.