Well, first of all, I’m sorry you’re suffering from post sinus drainage. I would gladly trade places with you, as I also have the sinus drainage, but I also have no taste or smell since December of 2022. I’ve had 2 Stellate Ganglion Blocks and they have only slightly helped, but am going in for a 3rd next month as this no taste or smell thing is a bore! It’s a long shot, but if you could have your Thyroid levels checked, that could be the problem. Ask your doctor to do the blood test to check your Thyroid levels. They should test your TSH, T3-free, T4-free and your thyroid antibodies. Mine were off the charts for hypothyroidism and Hashimoto’s and I never knew it. It’s a simple blood draw test and it will just rule some other things out. Good luck!