Your Libris needs time to charge and it is recommended that you set Libris in the charger for at least 4 hours while you are sleeping.
We do offer the Companion Pendant that is smaller and lightweight and can be work around the neck or wrist while sleeping. The pendant has a button, which when pushed initiates a call via the Libris.
For more information, please see the Companion Pendant section on the support main page.