Setting does not appear

Dear Madam/Sir,

I’ve downloaded and activated the reSmush.it plugin.

After searching for 15 minutes for the settings, I read https://www.ads-software.com/support/topic/where-do-i-find-settings-for-re-smushit/.

However, in the WP back-end in Media, there’s no reSmush.it link.

How do I resolve this?
I run WP 4.9.6 and WooCommerce 3.4.3.

With kind regards,

Luca