multi-db - Error establishing a database connection

Hi, I have followed step by step instructions to implement the multi-db (16) and edited db-config.php and move-blogs.php as per instructions.

When I run move-blogs.php, i got error message "Error establishing a database connection"

Also, my site is not working, it too provide that error message.

When i remove/rename db.php file , then site is working perfectly.
Using multi-db 3.2.4

Is there any solution you have?

Regards