Post name permalinks return 404

A duplicate of an old site was done and installed in a subfolder in a different domain but using same hosts. The front page at domain/subfolder/ appears fine but the other pages, using postname permalinks return 404. The permalinks do all appear to have updated to /subfolder/page-name etc but when going to one they return 404, file not found.

I’ve tried modifying the htacess but to no avail. The permalinks worked using plain permalinks but they’re not appropriate for the site. I’m unsure if now the issue is with that or with the server configuration and if I need to get in contact with the hosts.