[For 1.8] DVZ Mentions 1.0.6

[SvePu]

Installed this plugin and i get this error anyone able to help please
Runing mybb  1.8.31
And PHP Version 5.6.40 at least that's what it does say on mybb cPanel

Fatal error: Default value for parameters with a class type hint can only be NULL in /home/railwork/public_html/inc/plugins/dvz_mentions/core.php on line 5

This plugin requires PHP version 7.0 or higher. => https://community.mybb.com/mods.php?action=view&pid=29

[Harlock]

Would it be possible to "at" forum groups ? like discord does. That would be most helpful