“Unable to access wpconfig” error but confirm user is able

I get the error message “Unable to access wpconfig file. Please check if WordPress is installed on the destination address. Also, check if you have permission to access the folder.” but i have opened the site via filezilla with the user account used in the migration and edited wpconfig file without issue. Any idea what else this might do? Will have to look for a solution elsehwere if I cannot get this working!

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