When I went to TSB (UK) open an account for my partner and she was asked to type her password on their computer she asked when she can change the password, are

When I went to TSB (UK) open an account for my partner and she was asked to type her password on their computer she asked when she can change the password, are they any limitations, like wait 3 days before changing password. The assistant responded "why would you ever want to change your password? you can type any password you want now, just please type your password". This was so weird we didnt use the account for a few days, changed the password, waited a few days again and after that deposited money.