Why Potassium Bicarbonate has a higher solubility than Sodium Bicarbonate?

SODIUM BICARBONATE SOLUBILITY
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[Wiki](https://en.wikipedia.org/wiki/Sodium_bicarbonate)


[![enter image description here](https://i.stack.imgur.com/V8Rio.png)](https://i.stack.imgur.com/V8Rio.png)


POTASSIUM BICARBONATE SOLUBILITY
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[wiki](https://en.wikipedia.org/wiki/Potassium_bicarbonate)


[![enter image description here](https://i.stack.imgur.com/hcHFt.png)](https://i.stack.imgur.com/hcHFt.png)


As According to this [answer](https://chemistry.stackexchange.com/a/80460/105771)



> 
> Now, note that the hydride ion is "hard", having high negative charge
> density. While the carbonate ion is "soft", having a lower negative
> charge density.
> 
> 
> Applying the "hard-soft acid base" (HSAB) principle, we would expect
> the "hard" ions to form more stable compounds with each other and the
> "soft" ions to form more stable compounds with each other.
> 
> 
> Since the heavier alkali metal ions are softer, we would expect them
> to form more stable compounds with carbonate. As for the harder
> lighter metal ions, we would expect them to form more stable compounds
> with hydrides.
> 
> 
> 


As Bonding of Potassium and Biarbonate ions is stronger than bonding between Sodium and Bicarbonate( Aka Lattice energy) but the hydration of Sodium is higher than Potassium so according to my intuition when we dissolve Sodium Bicarbonate in water as its hydration energy is more it can overcome it small Lattice energy and it will get solvated by water further and get dissolved and the opposite should be the case for Potassium Bicarbonate, but Experimental answer is completely opposite? Can it be explained or it is a anamlous behaviour cannot be explained by current science


