Hi and welcome to the forum:
If you leave the battery in the camera for months it will almost certainly discharge - that is not recommended as a practice. If you have not done so, can I suggest charging the battery back up to full power and trying again?
To reduce battery drain, turn on Airplane Mode unless you are actively using WiFi or Bluetooth.
cheers, TREVOR
The mark of good photographer is less what they hold in their hand, it's more what they hold in their head;
"All the variety, all the charm, all the beauty of life is made up of light and shadow", Leo Tolstoy;
"Skill in photography is acquired by practice and not by purchase" Percy W. Harris
