Couldn't fetch mysqli() in AdminConfig.php during installation

I cannot complete Bagisto installation due to a MySQL error. Any help will be very appreciated.
System information:

Ubuntu 18.04 LTS
nginx: 1.14.0
PHP 7.2.19
MariaDB 10.3.17
NodeJS 10.16.3

Error message:

[error] 24308#24308: *177 FastCGI sent in stderr: "PHP message: PHP Warning:  mysqli::query(): Couldn't fetch mysqli in /home/user/bagisto/public/installer/AdminConfig.php on line 86
PHP message: PHP Warning:  mysqli::query(): Couldn't fetch mysqli in /home/user/bagisto/public/installer/AdminConfig.php on line 92
PHP message: PHP Warning:  main(): Couldn't fetch mysqli in /home/user/bagisto/public/installer/AdminConfig.php on line 95
PHP message: PHP Warning:  mysqli::close(): Couldn't fetch mysqli in /home/user/bagisto/public/installer/AdminConfig.php on line 98" while reading response header from upstream, client: 127.0.0.1, server: _, request: "POST /installer//AdminConfig.php HTTP/1.1", upstream: "fastcgi://unix:/var/run/php/php7.2-fpm.sock:", host: "localhost", referrer: "http://localhost/installer/"

Steps to reproduce:

Download Bagisto(v0.16) from GitHub
Follow installation instructions
Hit "Continue" button in Admin Details form
Expect following error

Notes:
Credentials are 100% correct since I completed previous step (Migration and Seeding).
Path to the public folder in error message text was modified as well as the second picture, for privacy reasons.

rahul

Hi @VorobiovM

On the basis of your attach screenshot, your installation has completed only admin details are not set & it could not established connection with database. Kindly make sure that you have entered all details correctly.

Thanks

vbanti

@rahul i have the same problem but i receive this error first....Warning: mysqli::close(): Couldn't fetch mysqli in C:\xampp\htdocs\bagisto\public\installer\index.php on line 107

Vaishali Agarwal

Hi @vbanti
Please check the mysql credentails are correct in .env file?

bagger

@Vaishali-Agarwal I am getting the same issue. Have fixed the emv file and keep testing alternatives with no success.

Vaishali Agarwal

Hi @bagger

login the mysql with command line and then run the command in CLI

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'Current-Root-Password';
FLUSH PRIVILEGES;
replace 'Current-Root-Password' with your password