Post covid ,for 5 months continuously I have nose blocks and sinus and breathing difficulties,lot of phlegm, severe ear pain and pain passes through throat and chest, when I met Ent doc he said eardrum is fine but still I feel lot of ear pain and pressure something is wrong with my left ear and back throat and pain passing to chest, and doc said DNS issues, What am I facing through? What further test to be done for my ear!.