Hi Stefano,
Wow, thank you so much for your prompt response! Please allow me to answer your questions:
1. I am using the 'Uncode' Theme.
2. In the footer the code I have for the list is [newsletter_form form=1] for English and [newsletter_form form=2] for the Greek versions of my footer. Should I switch to just [newsletter_form]? I did this because I wanted to make it more personalised for people by changing the 'SUBSCRIBE' button to greek language.
3. Regarding this page https://educraft.tech/el/newsletter-2/ I am not sure what's wrong. Indeed the button is grayed out but it's clickable.
UPDATE: By switch n2 to [newsletter] the accounts subscribed using the footer 'subscription form' are being subscribed in the correct list