If all investigations are normal you can help yourself.
Stop cleaning your throat in morning by fingers. This leaves a raw area to, which saliva sticks becomes dry and needs to be cleaned.
Do not hawk i.e. play music every morning with your nose and throat. Saliva becomes less fluid i.e. sticky with age and vigorous attempts to spit it are counter productive.
Keep warm water with green tea on your side in a thermos and sip it when you feel scratchy throat. Do not spit. The warm water will kill bacteria in your throat and the phlegm will become harmless.
Ask your grandchildren to remind you not to spit or hawk.