Talk to General Physician on Throat Infection

I've been suffering from some kind of throat infection since last 2-3 months.

When I got the infection first time, I took it lightly and didn't visit the doctor for one month or so and thought that it would get better on its own. But, it didn't go away so I visited a GP and she prescribed azi-once and neoday for one week. She also asked for the Rapis Strep A swab. The result was negative. After taking the medicines and waiting for 2 weeks, it didn't get better at all. I visited ENT specialist after that and he prescribed cefodox 200mg and divido for one week. He asked for culture and sensitivity throat swab and result was negative as well. I took the meds but they didn't work out as well.

Then I visited another ent specialist around 2 weeks ago and he prescribed augmentin 1g which I took for one week twice a day and it got a little better. But, as soon as I stopped taking the medication, the condition of throat is same again. I do the gargling with salt water couple of ti