Hi.
I'm trying to add a hyperlink to a button on this page: https://www.ashtutors.co.uk/newblog/entry/the-importance-of-learning-homophones.html

However, every time I insert it, then save the draft and update the post, the resulting button just links to the homepage of the site and vanishes from the block editor.

What's happening?

Many thanks.

Geoff

(This is the link I'm trying to add: https://www.ashtutors.co.uk/request-a-tutor.html)