Moving a Word Press Site

Hi,
I’d like to move a site from https://www.teste123.info/example1/ to https://www.lejardin.co.ao
which in the short term is on https://79.170.40.239/lejardin.co.ao/ until I can get live.

I’ve backed up the site and restored on the new server, the files and SQL database have gone over. I’ve tried to follow https://codex.www.ads-software.com/Moving_WordPress

I’ve changed the URL and Home in wp_options table in the database but still get Error establishing a database connection.
The tutorial mentions making changes in wp-config.php but I can’t see anything that needs changing?

Can anyone think of anything I’ve not done?

Thanks
Louis