Old sessions and customer carts will be stored in your database until they expire, so if you have modified the WooCommerce session expiration time in Clear Cart for WooCommerce, we recommend that you clear all existing WooCommerce sessions.
Existing sessions/carts will expire at the default WooCommerce expiration time, which is 48 hours of inactivity, or the previously set expiry time.
You can easily clear all sessions from your admin dashboard by going to WooCommerce > Status > Tools. Scroll down and click the Clear WooCommerce Sessions button. Once you’ve cleared existing sessions, your modified expiration time will apply to all new sessions.
Note that clearing all sessions will also clear customer’s carts if they are currently on the site.