Do I need to sign a new work contract if I change my mobile phone number? Does the WeChat chat record have legal effect? Answer: Don't you need to sign a new contract if you change your mobile phone number and other information? Yes. Why? The mobile phone number has little to do with the labor contract signed by the original company. What matters is your approval of the contract content, which you signed at that time. It's not the mobile phone number that has changed, but the contract. The change of mobile phone number is only used as a communication tool to contact units and individuals, which has something to do with the signing of the contract, but it has little to do with it. If you don't work in the company and violate the contract, the company doesn't update it in time because your mobile phone has changed. At this time, the mobile phone number and contact information have played a great role. The company will deal with you because you broke the rules. At this time, the mobile phone is very important. Therefore, the loss or replacement of a mobile phone must be reported to the company, which is the reason. Does her WeChat chat record have legal effect? If there is a problem with the signing of the contract, it will have legal effect as long as it is preserved.