AWS EC2 hosted wordpress , disk usage is increasing consistently

2020-05-23 wordpress amazon-ec2

I have hosted my website on AWS EC2. The website is built using WordPress. I am seeing weird behavior in my EC2 instance. The disc usage is consistently increasing even though I have not added or removed anything in the website.

root:/opt/bitnami/apps# df -h
Filesystem      Size  Used Avail Use% Mounted on
udev            1.9G     0  1.9G   0% /dev
tmpfs           391M  5.8M  385M   2% /run
/dev/nvme0n1p1   25G  4.6G   20G  19% /
tmpfs           2.0G     0  2.0G   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           2.0G     0  2.0G   0% /sys/fs/cgroup
/dev/loop0       90M   90M     0 100% /snap/core/8039
/dev/loop1       18M   18M     0 100% /snap/amazon-ssm-agent/1480
/dev/loop2       94M   94M     0 100% /snap/core/9066
/dev/loop3       18M   18M     0 100% /snap/amazon-ssm-agent/1566
tmpfs           391M     0  391M   0% /run/user/1000

I am concerned about this usage: /dev/nvme0n1p1 25G 4.6G 20G 19% /

Just 1 hour back, it's size was around 3.6G

What could be the reason here? How can I solve the problem?