Suscribe box/check on comments is not working

Hi,

I noticed that if I check the box to be suscribed on the comments Mailpoet 3 is not adding it to the suscribers list.

I tried on different browsers with the same result.

I’m using the last version of WordPress and Mailpoet 3. Here the detailed info:

PHP version: 7.0.26
MailPoet Free version: 3.3.2
MailPoet Premium version: N/A
MailPoet Premium/MSS key:
WordPress version: 4.9.1
Database version: 5.6.36-cll-lve
Web server: Apache
Server OS: Linux
WP_MEMORY_LIMIT: 40M
WP_MAX_MEMORY_LIMIT: 512M
WP_DEBUG: false
PHP max_execution_time: 300
PHP memory_limit: 512M
PHP upload_max_filesize: 55M
PHP post_max_size: 55M
WordPress language: es_ES
Multisite environment?: No
Current Theme: Imagely Ansel (version 1.0.6)
Active Plugin names: gravityforms/gravityforms.php, akismet/akismet.php, bloom/bloom.php, cookie-notice/cookie-notice.php, divi-builder/divi-builder.php, genesis-404-page/plugin.php, genesis-translations/genesis-translations.php, google-analytics-dashboard-for-wp/gadwp.php, google-analytics-for-wordpress/googleanalytics.php, mailpoet/mailpoet.php, meow-gallery/meow-gallery.php, re-add-underline-justify/re-add-underline-justify.php, regenerate-thumbnails/regenerate-thumbnails.php, smart-recent-posts-widget/srpw.php, so-css/so-css.php, subscribe-to-comments-reloaded/subscribe-to-comments-reloaded.php, table-of-contents-plus/toc.php, updraftplus/updraftplus.php, we-cachepress/we-cachepress.php, wordpress-seo/wp-seo.php, wp-external-links/wp-external-links.php, wp-featherlight/wp-featherlight.php, wp-smushit/wp-smush.php, wplr-sync/wplr-sync.php

I left the box activated on the url above in case you want to perform some tests.
I hope you can help me solving the problem.

Thanks!

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