Why files stopped uploading to a directory with 755 permissions on a vps hosting?

Question

CentOS

Rented a VPS with centos preinstalled. I logged in as root and created a new user username, on behalf of which I raised the site on wordpress. It worked for several months without errors, but today I could not upload the file to the hosting, although the directory had 755 rights. Raised the rights to 777 and the file was successfully loaded. However, instead of 644, he received 666-rights, and in the "owner" and "group" field, instead of my username "username", the name of the system user "apache" appeared.

What happened? Why can't I upload files with permissions 755 for folders and 644 for files as before?
And why when uploading files to a folder with permissions 777 instead of my username is now written "apache"?

Answer 1

but today I could not upload the file to the hosting

how did you download it?
umask is responsible for this
like this username2?
it does not display default users.
connect via ssh and see the output
Under what user is Apache running or who do you have there?