Recurrent Pain in Throat, yellow stone.

I am suffering from continuous pain in my throat, almost every one and half month I need to visit a doctor or in a medical shop to get some medicine. Usually doctors give some Amoxicillin or other antibiotics, betadine gargles and some other medicines but the problem is after taking this medicine get cured within 2 or 3 days then again I fell ill due to this and it's happening almost since 1 and half year or maybe more. I observed that there are yellow colour stuff formation on my tonsils I thought they are tonsils stone but doctor said they are just leftover food formation and I should just gargle daily. From my side I always gargle with salt water before going to sleep in my daily routine and if I don't feel well I do it with betadine. I got very frustrated with all of this that I decided to remove this yellow stone like thing with my finger, and after some time I bought one stainless steel tool to remove it, it somehow works.but problem is still there just it's now 2 and half month