Muscus every morning. Bent or allergic.

Hi, Initially I felt phelgm/muscus stuck in my nasal always.I used to spit out but nothing would come. This started before a 1.8years. visited ENT doctor,was told  this is bec  food / seasonal allergic and given nasal spray. It didn't help me. Consulted doctor again said now I'm having kind of breathing issue also ,was told it could be bec my nasal is not straight , bent bit , Advised to continue the same. Didn't help me. After 6 months went to another ENT, he also told could be food/seasonal allergic and gave nasal spray and some tablets. After some time my symptoms got changed. Only in morning after wake up will get muscus and more breathing issue after food ,especially after full meal.told the same to 3rd doctor and again was given spray by mentioning nasal bent or allergic.i forced doctor and took CT scan , was told no sinus prob, no permanent solution, continue spray.after six months (now) having same but muscus are thick in the morning , having tightness pain in left chest often