The disk usage limit is both on storage size (in GB) and on inodes. If you don’t know what an inode is, please see this article (spoiler: it’s not the number of sites):
If you need more inodes, please consider upgrading to premium hosting. Which considering that you paid $160 for a XenForo license should be a no-brainer.
And if you didn’t pay that for the license, please remember that using our hosting for pirated software is both illegal and strictly forbidden and will result in the termination of your account.
There are plenty of free forum options that also work very well, no need to become a criminal to create a forum.