Open Pinduoduo software, click on the personal center interface in the lower right corner, and then find the setting options. After entering the setting interface, we can see the mobile phone number options bound at the top. After entering the interface of binding mobile phone number, click the change binding option, enter the old mobile phone verification code, click the confirmation option, then enter the new mobile phone number and its verification code, and click bind now to successfully replace the bound mobile phone number.