Of course the scope sounds like a great idea if you never had Covid that you know of. I did have Covid, lost taste and smell for three months and then it turned to a horrible “metal mouth” like you’re sucking on a couple nickels, everyday, all day! So, after months of using salt water and learning how bad it was for me I asked my physician. Less than responsive, she had no idea. Told me to try Biotene. I found a product called Metaqil. Just a 1/2 teaspoon helps alleviate the horrible taste. Additionally I have started using a product called “Allday”. It consists of an artificial sweetener that helps you salivate, just spray on tongue and rub tongue on teeth and gums. ( No saliva is bad for your teeth and gums. ). I’m now in my ninth month of this. Wishing there was a cure, but beginning to accept this may never go away.