If the problem is more serious like Hypothalamic dysfunction, mentioned by
@Pyrrhus treatment would be really difficult, but for some % there is easier explanation which is totally curable:
so the whole thing is thanks to my knowledge on bodybuilding/martial arts, that i was doing in the past, hormones, that are in control of our water managment(like f.e. vasporesin) work in kind of feedback loop:
Lets say we start to drink more water b/c we read that it is healthy, after body realize that there is a a lot of water in a system, it produces hormones which signal, that we should get rid of excess fluid, so we pee a lot then BUT there is reverse system and peeing a lot makes our body 'afraid' of losing to much fluids so body also produces hormones to help regain lost fluids and the way to carry that out is to make us thirsty(by secreting those hormones).
So we have a spiral here- we start to drink more water -> it makes us pee a lot -> peeing a lot makes us even more thirsty -> we drink more -> we pee more -> ... .
Reseting the system takes usually 2, 3 days and that's why, as i mentioned earlier, it is used in martial arts like mma, kickboxing, jiu-jitsu etc., where fighter want to lose a lot of weight in short time, to fit in lower weight-category,
the protocol looks like this- they start to drink horrendous amount of water(sometimes something like 10 liters/day) one week before competition, of course it causing them to pee a lot, around 2 or 3 days before weight-ins they drastically stop fluid consumption BUT body is still accustomed to huge intake of water, so during those last two days, even that fighters are not consuming almost any fluids, they still pee a lot(like they would still drink those 10 liters per day), so during last two days they can lose up to 10kg in just water(b/c 0 fluid IN, a lot of OUT)
*obviously fighters add some extra things like limiting carbs, to lose glicogen from muscle that binds a lot of water too, sauna, hot baths, etc. but it doesent matter at the moment
So fighters use this water_managment resesting time-gap, for their good but sometimes it works against us, b/c it can make someone 'artifically' thirsty,
good part is that coming out of this cycle(lot of drinking and peeing) is quite easy and it also takes around 2 to 3 days, what we need to do is just to limit(and by limiting i dont mean not driniking anything but drinking less) the fluid intake despite the fact that we are thirsty, b/c this thirst is not symptom of dehydration but hormone imbalance, after two days it should regulate or at least there should be improvment, we can also go through the process gradually, just be limiting water intake just a lil bit during longer period. Hydration of the body stays on the same level, we are starting to drink less, but also pee less and what is most important(im not 100% about this) we are not losing so many electrolites in out pee
