issue with Unite Revolution slider 2

i bought progressive multipurpose template few hours ago, installed successfully on my hosting account. I got this error "An error has occurred.> 0 [] operator not supported for strings" when I tried to open Unit Revolution Slider 2 in component from my joomla backend.
kindly advice on what to do please.

Thanks.

Hi @abujidaa,

Please contact the author of your purchased Joomla Template, the Template author will assist you.

How to contact an author to get support or for any technical query:

Thanks

As per the UniteCMS ticket site (see here) and an older Envato forum post (see here) I believe that error is a conflict with your PHP version, most likely due to using an outdated copy of your slider plugin. If you purchased the plugin yourself I would suggest updating to the latest version. If instead the plugin was bundled with a premium theme then reach out to the theme developer to see if they can either push out an update or send you the current version of the plugin directly.