My ec2 instance struck in PENDING state when starting

I got the following error message when checking the instance detail.
Volume impaired
Some of the volumes attached to instance i-018b5f60aef89fda are impaired. Please review the state of your volumes.
The volume is in "attaching" status for a long time.

I can't terminate the instance as I don't have any data backup. How can I start the instance or create an image if have to terminate it? The last stop process was normal and stopped properly. There was no configuration change after that. Appreciate if any one can help recovering the instance or save the data, thanks!