Can't log to dashboard anymore, tried many things

I’ve been Googling and searching this forum before posting this. I really don’t know what to do.

You’ll find solutions I already tried below.

* Background:

I’ve been hacked, so I restored my websites from an auto backup and manually tried (and managed) to add a double auth with .htaccess.

I’ve also updated all of my websites to the very last version of WordPress, and all plugins too were updated.

Then, the .htaccess was troublesome and I wasn’t able to enter the dashboard one of my website anymore, so I get rid of it.

But it seems that .htaccess/.htpassword wasn’t the cause of my inability to enter my dashboard because I still can access the dashboard of all my sites, except one!

* The problem:

Now I don’t have .htaccess/.htpassword for this domain, yet when I enter :
https://raccourci-minimaliste.com/wp-admin/

it is automatically redirected to:

https://raccourci-minimaliste.com/wp-login.php?redirect_to=http%3A%2F%2Fwww.raccourci-minimaliste.com%2Fwp-admin%2F&reauth=1

Then, whether I enter a correct or incorrect login, it redirect me to:

https://raccourci-minimaliste.com/wp-login.php

But it display my website, NOT the login page!

If I reload it, it display indeed the login page, and the same problem appears again, whether I enter good or bad ID, I’m redirected again to https://raccourci-minimaliste.com/wp-login.php displaying my website, not the login page nor the dashboard.

* What I already tried:

* Reinstall fresh WordPress and restoring SQL: it did work! I was able to log in into my dashboard, great! So I disconnected. Then, without having done anything else, I tried again to log into my dashboad and the same problem happen again!!!:O

* Tried with Firefox instead of Chrome, on different internet connections too. So it’s not a cache or cookie issue.

* Deactivated plugins and themes (via FTP)

* In the PHPMyAdmin database of wp_options, the url is correct

* In wp-login.php I’ve put:

require( dirname(__FILE__) . '/wp-load.php' );

update_option('siteurl', 'https://raccourci-minimaliste.com' );
update_option('home', 'https://raccourci-minimaliste.com' );

* In wp-config.php, I’ve added:

define('WP_HOME', 'https://raccourci-minimaliste.com');
define('WP_SITEURL', 'https://raccourci-minimaliste.com');
define('DOMAIN_CURRENT_SITE', 'https://raccourci-minimaliste.com');
define('COOKIE_DOMAIN', 'https://raccourci-minimaliste.com');
define('ADMIN_COOKIE_PATH', '/');

Something interesting to notice is that the permalinks to my articles doesn’t work anymore and lead to 404 errors!

Try to click to any entry of article in my blog you’ll see.

And here I am, I have absolutely no clue of what to do anymore to go into my dashboard again…

Thank you for your help.