According to:
https://www.siteground.com/kb/how_to_install_moodle_on_my_account/
"You need help with an application? SiteGround is specialized in hosting and supporting more than 200 scripts. Sign up for our web hosting services and let us help you with your application, 24/7!"
Moodle.org doesn't program the script you use to install/update/upgrade thus there is no forum for such either here in Community forums.
You might check out:
https://www.siteground.com/tutorials/moodle/
and if that doesn't help, contact SiteGround help desk.
'spirit of sharing', Ken