Photoshop CS5,can not type in multiline in one textbox in one layer error solved

I faced this irritating issue,

Here how it got solved

I reset the character panel(click on the rightmost symbol at the top of the character panel).

Turn off the numlock.

Right click on the the first arrow sign from left under file and then Reset tool or Reset all tools.

and then I seem to type multiline on a textbox in just one layer