Multisite URL error

I activated multisite on an old WordPress installation more than one month old. As usual (so I found out) WordPress didn’t allow me use sub directory it instead allowed setting up the network using subdomain.

Site1.yourdomain.com

I did that at first but then I started having ssl error issues accessing the subsite, also I had login issue so I edited the .htaccess file according to what I found here on journalxtra.
This is what my .htaccess file looks like here

I decided to do the network set up again using subdirectory(I forgot to deactivate all plugins when I did this).
According to what I found on Google, I edited a code in my wp-config.php
/******/
define( ‘WP_ALLOW_MULTISITE’, true);

define(‘MULTISITE’, true);
define(‘SUBDOMAIN_INSTALL’, false);
define(‘DOMAIN_CURRENT_SITE’, ‘grandmotivation.com’);
define(‘PATH_CURRENT_SITE’, ‘/’);
define(‘SITE_ID_CURRENT_SITE’, 1);
define(‘BLOG_ID_CURRENT_SITE’, 1);
/********/

It worked and I was able to create new subsites with a url looking like

Yourdomain.com/site1

But when I create and delete a new site, the url “mydomain/site1/wp-admin” shows the admin dashboard of my original site “mydomain/wp-admin”

I tried creating more sites and inturn deleted them to test that, and all of them were returning the dashboard of my main site even after deleting them,
E.g all 3 domains
mydomain/site1/wp-admin,
mydomain/site2/wp-admin, &
mydomain/site3/wp-admin.

Now shows my main dashboard located at
mydomain/wp-admin.

Additionally if I create a new subsite “mydomain/site1/” and I set it up normally and it shows the website.
When I create a folder inside cpanel under public html with the name “site1”, the url “mydomain/site1/wp-admin” stops showing the website I created, it instead starts showing the contents in the new folder.

I noticed this when I decided to change a subsites url using wordpress built in function under sites settings, though I had tried using WP MU domain mapping plugin but after configuring it, when I tried changing the url and I saved it, it returns success message that new domain is added but the new domain name never shows.

I think I have messed up with something but I don’t really know it as I’m new to creating multisites.

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