Joomla! Template AT Health - Item Support

i have installed the quick version, and updated joomla to 3.6.5, if i try to update to 3.8.1 i receive HTTP ERROR 500, and i can't access the administration panel, the site works.

Any information on how i can fix this ?
i can't manage to edit the social icons links and to modify the copyright.

in the advertise i read before purchase say that i can edit those informations.

Please help.
Item Name:
AT Health
Author:
Downloads:
130
Sales:
30
Created:
2015-08-12
Updated:
2016-12-27
Item Version:
2.0.0
$29.00 $21.75
Regular License
This item may be used for a single domain only.
$39.00 $29.25
Extended License

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