My dad has been on oxygen for a few years now for COPD. Lately hes been having a hard time keeping his oxygen levels at a consistent percent. Today they've been really high, like 97%(which is much higher than it usually would be), this is with his machine barely turned on, but when he goes to do anything, like lay down, it will drop to like 87%. Just wondering why this is happening or if anyone else has experienced this problem. Any tips on how to keep your oxygen at a constant percentage? I tried googling, but unfortunately, I couldn't find anything helpful. Also what is causing his oxygen levels to be higher lately? He says they seem too high, like he's getting too much oxygen, but like I said, he barely has the machine turned up, and his levels don't stay where they should