Hai mama, this is actually quite common in pregnancy, hormones can cause the nasal passages to swell and get congested, so don't worry you're not alone! But since it's been going on for a while, it might be good to check with your doctor just to make sure it's pregnancy rhinitis and not something else, especially if the phlegm is thick or discoloured. In the meantime, try sleeping with an extra pillow to elevate your head, and saline rinse or a humidifier can help ease the congestion safely during pregnancy. Take care of yourself ya!