Why can't I change my pin?
Sorry for the late reply! You did not provide your name or barcode number, but looking up the email you used, there is an item ready for pickup for you (if that is your email). You can always call any branch to ask about a hold, too. When you go in to pick up the hold, you can reset your PIN at the same time (bring a photo ID). Normally you should be able to reset your PIN by clicking on the "forgot your PIN" option on the log-in screen; the system will send a link to the email in your library account to set a new PIN.
Let us know if you have further troubles!