Sinusitis (allergy) Please advise me.

Hi Sir/Mam, It's been more than 10 years I've been dealing with a consistent issue of producing white mucus in my saliva every day. Oddly, when I consume spicy foods, it seems to trigger the expulsion of the mucus. However, on other occasions, it remains trapped in my chest and throat, leading to a feeling of heaviness in my head. Additionally, I've noticed an excessive buildup of acid in my body, resulting in frequent belching. Alongside these symptoms, I frequently experience nasal congestion and a sense of heaviness above my eyebrows. I've been wondering about the potential causes behind these symptoms, such as acid reflux, allergies, sinusitis, or respiratory infections. I have consulted multiple doctors; some have suggested that it might be sinusitis, while others believe it could be allergies. I have been prescribed anti allergy medication such as Montair LC and nasal sprays, but unfortunately, they have not yielded any positive results. Please advise me. Thanks