You typed the same value for the current and new Tax ID/CPF. But they must be different.
If you want to change your CPF, you must return and type the correct Tax ID/CPF you want in your account when prompted for it. It must be the same as shown in your government documents. Also, return to the screen where you should type the current Tax ID/CPF of your account and type it, the incorrect one. To find it, open the website and click on "Deposit". Your current Tax ID can be found under the PIX or bank transfer options.
If you don't want to change your Tax ID/CPF, erase one of the fields, return to the first screen and select only the options you want to change.