To help increase your hubber score, you can participate more in the HubPages community by publishing hubs, commenting on other people's hubs, asking questions, answering questions, posting on forums, etc.
It's normal for hubber scores to fluctuate up and down though. You can find out more by reading the learning center guide on hubber scores. Here's the link: https://hubpageshelp.com/content/Learning-Center-h... . Hope this helped.