Thanks @ashishsthanp. I changed to default theme 2017 but had same issue. Then I went back to Spacious and adjusted Settings/Reading. I increased the number of posts visible on a Blog page. Not sure if this helped but what did seem to fix it was deleting the WP Cache with ‘WP Fastest Cache’ plugin. This also solved a second issue with an old header image still showing, despite my deleting it. It seemed to be a WP issue rather than with the theme.