This sound like a bad redirection which is easy to address.
Delete the .htaccess file from your site's root, and your administrator directory. Copy the htaccess.txt file shipped with Joomla (it's in your site's root) to .htaccess in your site's root. Please note that both of these actions can be taken when restoring your site, Site Setup page, top right box in the main content area.
Edit your configuration.php file. If your $live_site is not empty, change it to be empty:
public $live_site = '';
Please note that this can also be done when restoring your site, Site Setup page, it's the Live Site parameter. If you click on the button to show the help you'll see it tells you that on most servers it should remain empty.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!