Partial loss of smell ( Covid or cold ID

Had cold back.in 25 apr 2021 Lost smell on 5th May Cold was not getting better till 30th.After the cold gone Felt strange heavyness in nose. Went for the CT scan about 2 w eks ago. It showed hypodense mucosal thickening in left maxillary. Left maxillary sinusitis, maybe. Doctor tried allergy, antibiotics meds. Now on antibiotics and steroid for 8 days. Heavyness is little better. But sense of smell is very little. Doctor says might allergy, the allergy can be controlled by meds but he did not say anything about loss of smell. I think he said no guarantee for smell. I can smell strong odor and isolated strong taste ( such as elaichi) but food is not easily recognisable. How long will it take to recover? Anything else can be done to speed up recovery? Is it permanent, I am worried.