Volume Resize
1. Check up
Goto Project > Compute > Instance > Console, Check the volume status, make sure it's unmounted
2. Detach the volume
Goto Project > Volumes > Volumes, select the Manage Attachment
from the Actions column and Detach the volume from the instance
3. Extend volume
Goto Project > Volumes > Volumes, select the Extend Volume
from the Actions column and set the new size.
4. Attach the volume
Goto Project > Volumes > Volumes, select the Manage Attachment
from the Actions column and attach the volume to the instance
5. Result
Goto Project > Compute > Instance > Console, Check the attached volume status