Expand Text not working

Hi
I have written a post at https://eatonfamily.website/mobile-phones/ with the text:

[su_expand more_icon=”icon: arrow-down” less_icon=”icon: arrow-up”]

This text block can be expanded

[/su_expand]

…but it does not render the hidden text part, instead it shows it like:
This text block can be expanded
Show more

Any ideas about what is going wrong?

Thanks.

https://www.ads-software.com/plugins/shortcodes-ultimate/