Which law did the notice of water stoppage violate?

According to Article 45 of the Property Management Regulations, water supply, power supply, gas supply, heating, communication, cable TV and other units shall charge relevant fees to the end users in the property management area. Where a realty service enterprise accepts the entrustment to collect the fees mentioned in the preceding paragraph, it shall not collect additional fees such as handling fees from the owners. Your water supply and power supply has nothing to do with the property. Water cut-off is the business of water supply department, and power cut-off is the business of power department. Unless the property has a power of attorney from these departments to let you cut off water and electricity, the property is illegal.

Legal objectivity:

Article 944 of the Civil Law, the owner shall pay the property fee to the property service provider as agreed. If the property service provider has provided services in accordance with the agreement and relevant regulations, the owner shall not refuse to pay the property fee on the grounds that he has not accepted or does not need to accept the relevant property services. If the owner fails to pay the property fee within the time limit in violation of the agreement, the property service provider may urge him to pay it within a reasonable period of time; If the payment is not made within a reasonable period, the property service provider may bring a lawsuit or apply for arbitration. The property service provider shall not stop power supply, water supply, heat supply and gas supply to demand payment of property fees.