wp-admin not working

We have the ftp login details for the site “lauramaroldimanagement.com/dev”.
From the ftp, we have got the username and password for the database used in the site.
From the database, we have got the username and password for the wp-admin.

But when we try load the wp-admin “https://www.lauramaroldimanagement.com/dev/wp-admin/”, the url is not working.

Could you please help us how to resolve the issue?

This is my client’s website. He only knows the ftp login details.

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