Urgent help Disc usage is high

Hello folks

I need urgent help.

My admin panel in VPS is showing that Disc usage is
141GB / 150GB

So right now is 141GB and that is not correct. I have checked and count all Disc usage’s for every domain in C-panel’s and result is 108,5GB.

I was contact server support and they said:

Thank you for being connected.
1.I have checked this for you and the monitoring tab in server shows disk usage is high.
2.It is getting exhausted because some application/plugin is over-utilizing server resources, even more traffic on site could be the reason for the site to load slow.
3.If there’s a problem with your site- a runaway script, a poorly configured plug-in, or a process creating too many files or directories in your account it will automatically use the disk space, I will request you to review and optimize your content or upgrade the server for more resources if you are experiencing more traffic/visitors on site.

My opinion is that plugins can’t eat server resources,and scripts that can only eat CPU and RAM.

Did anyone can help me about this problem.? I not have heavy traffic at all,i mean i only have 600 users daily and there is no one who upload files to fill up Disc space at all,only me as admin.