Well I have never had symptoms, but I’ve always had sodium that’s a little low. I could only limit my liquids so much without being miserable, so they prescribed salt tablets and taking two of those a day have taken me into the normal zone for the first time in many many years. Plus I continue to drink plenty of liquids. So maybe you could ask for salt tablets as well and see if that helps?

In my aged father's case, and he learned his elder sister was the same, they take salt in a glass of water. My father drinks water like a fish....all day...meaning he flushes out many elements, including sodium if the kidneys can't quite keep up. So, he was advised to take a pinch of salt in all of his water. He doesn't really like it as it tastes weird, brackish, but it keeps him out of hospital. As an old man who fell badly three times last summer, once breaking a vertebra, we convinced his GP, who actually came to his apartment to check on him, to order a test every two months to ensure he wasn't slipping, or going the other way...to much. It has been nine months now and he feels fine, no symptoms (enough to feel awful, bad enough to ask to be taken to the ER).
This time of year, as an outdoorsy guy who gardens, often in the noonday sun, I sweat a lot. I also go for aggressive long walks in the afternoon, no matter the season. This means my hat and clothing look crusty when I return. So, I eat some chease, salt my coffee some, and generally make sure I don't go wanting. I had that happen as a teenager working in the summer heat cutting jackpines (lodgepole) at a mine where they did blasting in an open pit. They needed stoppers for the tops of the holes into which prilled (correct spelling) ammonium nitrate was poured to make the explosion, and those were always a short length of jackpine, which grew all over the place in vast numbers. That summer, I was the lucky sod who got to cut them, peel them, and stack them. I drank a lot of water from a sweating canvas bag (the evaporated 'loss' out the sides of the bag kept the contents cool). It only took a few days and I began to feel terrible. Cramps, nausea, lack of motivation (to return to the job). I saw a doctor who diagnosed lack of salt. Didn't even need a blood or urine test.