Hello all

My N900 it's 4 years old now and since last week, it doesn't charge like before.
I charge it like all night (8 hours), and then the batery only lasts only like 4 hours with low using. After that, the phone just goes from full charging to empty and then turns off. To turn it on, I must conect it to the charger, or else it's impossible to turn it on.

I'm making this post to ask your opinion.

-Should I replace the batery for a new one?
-Is this a software problem and a flash can solve it?
-Should I just buy a new phone? (I don't want to xD!!)

Please help me!