Cloning a site 5.7

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Hello, I developed a site under 5.7. I try to clone it within the same account under an other site-directory WITH INSTALLATRON. I get an error doing this ?

Erreur
Unable to detect the source installed application's database information. Please contact support for assistance.

Every thing is ok with Version 5.6

Could you give me a way to clone please. (seems to be with PHP admin
Thank you

Claude-Alain