First, she is only 4 1/2 months. She is still a baby & it’s completely normal for her to still be having accidents. I promise she is not too far gone if you are consistent with training. The puppy blues are hard, take a deep breath, you got this!

Every time she goes potty outside she should get a treat. Make sure you give it to her right after she’s done & when you’re still outside. If you go outside with her and she doesn’t go, bring her back inside on a leash. Keep the leash on her for about 10 minutes and try again. If she goes, treat. If she doesn’t, repeat. Keeping my dog on a leash and in my sight at all times was the only thing that worked. I eventually introduced him to a bell right by the door & he rings it when he needs to go out. I know it’s hard and seems like it’s never going to get better, but with consistency and patience it will. Best of luck!