I am currently at work until tomorrow and I am unable to provide more details at this time. However, please try the following:
Replace the content of the .htaccess file in the root directory of your website with:
Code:
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteRule ^(.*)$ public/$1 [L]
</IfModule>
Instead of using the Newtaxi tutorial, follow the Ridein tutorial. Verify that all Firebase-related fields are correct and that the Firebase database rules are also correct. Add the SHA1 and SHA256 (release and debug) of the apps to Firebase. Download the google-services.json files again and upload them to the respective app folders. Also, download the Firebase service account private key .json file again and upload it to your admin panel. Finally, if you are testing your panel on a VPS server, renew correctly the SSL certificate for your domain, believe me, this is very important.