When I go to our website the error "Error establishing a database connection" displays. I already checked our wp-config settings and database and couldn't find any issue.
Can you please help?
First let me say welcome to the community!
Looks like you might have worked out the issue as I'm not seeing the error displayed on your live site linked above.
Can you let us know what you did in case any other member encounters similar issues with their own database connections? I'm sure they'd appreciate your solution to this as a suggestion to help them out as well.