Advice baby congestion

My son is 5 months old. He has been congested so much of his life I feel really bad about it. His pediatrician just tells me to use saline mist in his nose then use my nose frida to clean it out. So I do. I take him in the steamy bathroom for a few minutes as well. I’m not sure what to do and it’s been going on most of his life. I mean it’s not constant 24-7 he’s congested it goes away, then comes back. He coughs it used to be a couple little coughs but now he can cough more. Honestly I feel like I’m not doing a good job as a mom. I been thinking about getting a different opinion from another pediatrician

Now a back story. We live in a finished basement. We use a dehumidifier because basements are more on the damper side. His pediatrician said stop taking the water out of the air so we stopped using it for a couple days. Also they say to use a humidifier it will help break down the congestion. I thought that wouldn’t work well because of the basement. I’m not even sure if it’s the basement at all. I’m just hoping someone can give me some advice here.