I have the same issue here:
https://ww.wp.xz.cn/support/topic/using-plugin-just-gives-404/
Tried changing my permalinks also to no avail.
Over on Nginx Unit’s github – It appears that this issue is due to an outdated SSL Protocol with wordpress Site-Health function.
Heres the github:
https://github.com/nginx/unit/issues/282#issuecomment-513868101
Can anyone shed any light on this?
As a note – I am able to upload via SFTP and change themes / images etc that way – Just not from the wordpress dashboard
