You will need to provide the new account number and sort code to your employer or DWP/benefits provider, do this with plenty of time as soon as you are notified of your new account number and sort code, this will ensure the payments are processed to your new account and nothing is delayed. See our handy guide of how to do this here.
Once you have provided your new account details to them, please activate your new card. If you activate the new card without updating your account details with your employer or DWP, your payments may bounce back.