Yes, you can change your mobile number at an ATM, but the specific process will depend on your bank. Here's a general outline: 1) Check if your bank allows mobile number change through ATM 2) Locate an ATM of your bank 3) Insert your debit card and enter your PIN 4) Select "Mobile Number Registration" or "Change Mobile Number" 5) Enter your old and new mobile numbers 6) Verify with OTP 7) ATM will display a confirmation message