Secondly, if you can't get a satisfactory answer, you can complain to the local market supervision and management department or the consumer association. These institutions usually have staff who are specially responsible for dealing with similar problems and can give more authoritative and effective help.
3. Finally, when you complain, you must keep relevant evidence and describe the problem in detail. If necessary, you can also invite third-party professionals (such as architects, engineers, etc.). ) Conduct on-site investigation and issue appraisal report to enhance your persuasiveness.