Enable Logging? Contact Not Adding to CC List

We are using Constant Contact + WooCommerce version 2.3.2 and have noticed accounts not syncing to our email lists. We have a checkbox enabled on the checkout page and have tried historically importing customers from past orders. The email lists do look to update, but the last few customer email addresses don’t show on any of the lists. Is there anyway to enable logging to see when emails are being synced with constant contact? I checked the logs under Woocommerce > Status > Logs and there isnt any logs shown for your plugin. We just want to make sure the form is working as expected. We recently reconnected the account and synced customers again.