Posts shown totally instead excerpts

Hi,

I’m unsure if this problem fits the section, but I’d like to get a solution to this – after a 20 minute inefficient searching.

My site: https://www.talkourdogs.com

Using the Twenty Two theme, in Reading Setting I clicked to show summary – instead full posts – to speed up loading time. But, the site shows only the full posts.

Please, would someone be so kind to lead me into the right direction, what to do?

Thank you,

Alex