Dry Small Coughing. Or treatment!

My sister is having prolonged small dry coughing in evening every day. She had fever around 21st April and was gone in 3-4 days. Her Blood oxygen saturation level is also fine (around 96/97 now) On 5th May she was feeling very weak and a little feverish so upon recommendation of some doctors we have had her CT scan(attached). Now she is not having fever but generally in evening she starts continuously small dry coughing for some time. She also had little pain in the collar bone. No throat pain but she feels like having cough stuck in throat. Currently is is only taking Montelucast sodium and Levocetrizine but it seems to not help. She is still feeling weak and hands are shaking. Can you please support here with some medicine or treatment