This almost always happens because of the bookmark you have saved in your browser. If you look at the bookmarked link and it has the date when you first started planning, you will just need to change the link to have no date! (Or to bookmark your home page.) This will allow your planbook to always open to the current week.
Note: If you continue having issues after trying to log in multiple times, please reach out to us at firstname.lastname@example.org so we can help resolve this issue!