Phlegm in my throat and post nasal drip after Covid

Ever since I had covid in January of 2022 I recovered from the virus but I was left with a constant phlegm in the back of my throat and post nasal drip that will not go away. The feeling of having mucus in the back of my throat actually gets worse when I try to get rid of it by coughing. I have been given steroid inhalers, albuterol, allergy medication, but none of these work. The mucus gets worse especially after I eat. I've never felt like this before and it all started after covid. Can anybody relate to what I am going through?