Bills and bill payments are not available in the Free and Standard plans of Zoho Books. Ensure you have subscribed to a plan that supports these features. You can refer to our pricing page and plan comparison link for more details.
You can upgrade your organization to the Professional or a higher plan to use these modules. However, if you prefer to continue with the Free/Standard plan, you can record your purchases as Expenses, and they will reflect in your reports accordingly.
Books
Online accounting software
for small businesses.