You may have snozzled things up, trying to install stuff repeatedly.
Try deleting the installation.
Then either use your FTP program or your SSH client and change the name of your domain’s directory to something else, and create a new directory with the old name. That way, you’ll be sure there’s nothing in that directory.
And then perform a new installation.
I can’t guarantee that’ll work for you, but as they say, a kind word and a billyclub will warm the heart of any scoundrel. (When I first hosted here, around the turn of the century, I was on “Jezebel”. It seemed a very appropriate name. Servers are treacherous females. Now, I’m on “bonk” - and you can guess what I’d frequently like to do to the server…)