Posts: Manual excerpt not working

I cannot seem to get the manual excerpt to work in my posts.
Adding the “Read More” block works, but in some cases I want a separate text for the excerpt.
I have tried adding this in the manual excerpt box within the post editor, but it does not work. The full post appears.
Any ideas?

Good morning

Sorry, but this is how it’s designed, there is no option to change this from the options panel

Hi Noda,
Thanks for your response. What I’m trying to say is the ‘Excerpt’ option, which exists in the document options (along with tags, featured image, etc) does not work. See attached.
When I try and use it, it seems to do nothing. Only by using the ‘read more’ block will it work.
All information on wordpress’ website says it should work when content is entered.

Alan, im sorry, i understand your question but unfortunately, i have nothing to offer because this is how theme coded and at this moment I can’t offer any solution