&bethfjohnson33 You could try positional drainage. There are sites online for techniques since people have mucus plugs in different lobes or areas. Lying on your back, side or stomach could work. You breathe in for a count of 4 or 4, hold breathe for same, then I exhale, engaging my diaphragm and it rattles your lungs. Sit up and huff cough, or hold breathe again and huff cough then. Repeat until you’re satisfied that you’ve removed enough phlegm. Hope that helps.
I use NAC, (600 mg) an amino acid, twice a day which helps thin mucus. Hope that helps.