Oh!
It failed for me once yesterday then it worked,,,

Today, the same.
I'm using a chrome browser on an android tablet.
Working if I just paste in
www.shanty-songbook.co.uk

https://shanty.epizy.com/
dated 2022-2024
seems to work for me today

&
http://www.dave-wheatley.org/songbook/0-pages/about/about.html
works

but I notice they have an exclamation mark in a black triangle in the left of the url box
"denotes that your Site is using http and not https"

idk are some browsers more careful than others about what they'll open??
Beyond my knowledge!