What Causes Constant Blockage In Throat?

iv had this blockage in my throat for 6 years now,and it seems to be getting worse iv had my gallbladder out as i have avcid reflux but it just seems i have so much phlegm caught in my throat i cant stop clearing my throat constantly i make myself sick at least once a week to try and shift it but to no avail im 45 and overweight and have sleep apnoea as well i would love a second opinion thank you.