Phlegm after eating food. Any food?

Is it normal to get a teaspoon of grey and sometimes transparent phlegm (not black) after eating any food? I m getting it since a month. Whenever I eat something, right after I finish eating, I get phlegm automatically! It didn't happen before. I used to live in Himachal, I shifted to gurugram in Jan 2024. Then I travelled by AC sleeper bus 3 times since then. Whenever I travel by an AC sleeper bus my throat starts to pain and I get cold. But when I wear a mask all the time in an AC bus, I don't get any cold. Since Jan 2024 I got cold 3 times and since then I have this phlegm thing going on. I even had black particles phlegm for few days then it stopped coming black, it came grey and transparent. In my last cold I was prescribed Azithromycin 500  qd for 3 days and an zadonase qd for 5 days. Cold is gone, sore throat is gone. But the phlegm is still there, everytime after I eat food.