WHM Cpanel / AWS hosting, this partition is full, how?

I've got this hosting account with AWS, and I had a partition that was getting really full. So I hired someone to create a new partition and he showed me how to migrate a few accounts into the new partition.

I thought this would bring down the amount of data that was in the near full partition, but it hasn't.

See from the screenshot, what is called 'home3' is totally full, and 'home4' (the new partition) is slowly filling up.

I'm assuming home3 is full of backups or something.

How do I clean up home3 without messing with command line tools? Or, do I need to hire a real pro to do this? Is there something in WHM that allows me to do a clean up? Because if there is I can't find it.