sleep of death problem in Xperia M

[Joydip]

My Xperia M phone suffered 'sleep of death ' today. I reboot the phone by replacing the battery. Advise how I can fix the bug. I have latest software installed

[Thommo]

How often does this happen as this is normally linked to or starts after an app is installed and would be caused by said app like these stupid battery saving apps

[Joydip]

Nothing installed recently. It was occurred while charging the phone.

[Joydip]

It was happened for once.