Baby congested

My baby girl is 8 weeks old and so congested. She wakes up sometimes coughing like she has mucus. We use a nose Frida and nasal spray but it seems to be in her throat? Or post nasal drip? Anyone have any advice? Any similar experiences? What can I do to help her and will it go away as she gets older.. ER said her lungs are clear and she "looks great" just congested and suggested everything we are already doing so perhaps some other mamas may have remedies we haven't tried 🥺