Short code not showing for Mail poet unsubscribe link

I have followed the instructions for embedding the short code into an unsubscribe page for the link to mail poet unsubscribe: [mailpoet_page]

But this link is not visible, it is present, but it is not visible. I have researched forums discussing this and I have eliminated the issue of checking this via an email sent to us and it is still not visible. Is it possible we have a conflict with our block plugins?

I say this because when we add a hyperlink to text on any page, the text disappears and this is something we are trying to resolve too. Possibly the problem is one in the same?

Looking forward to some ideas from those more knowledgable than ourselves