We were having problems with Jenny and found out she had a bladder infection. You might want to rule that out. After she got an antibiotic she never had another accident. She is about the same age. If that isn't the problem then you may need to crate her indoors unless you are actively engaged with her. When you see her peeing make a loud noise and scoop her up and take her out. Also make sure you are cleaning the spots she has peed on inside with Nature's Miracle or something similar so she isn't attracted back to the same spots.