Clients website not uploading

[Polly360]

Hi,

I was trying login my client's website, and it's not even letting me enter the admin page. 
the website is - http://bdeng.com.au/admin/

What could be the issue?

Thanks

[moderator note: link has been edited - was: https: //track.mailalert.io/t/9f6f0e98-0160-4996-bd8e-7adeee00e538/?url=http%3A%2F%2Fbdeng.com.au%2Fadmin%2F ]