Hello,
Thank you very much for choosing our theme and for contacting us.
There may be two reasons: the site is created because your host capacity is not enough for such a heavy site or another reason is the conflict between the plugins or plugins with the theme.
Please contact your support first of all and make sure you have the capacity enough. Then install the plugins one by one checking the site.
Some of our users have 40-50 plugins active and site works.
Best Regards