And if your physical banknotes do somehow get damaged e.g. by fire or by being chewed by a pet, there is a decent chance you'll still be able to get them exchanged, because there are government-backed institutions there to help you such as the Bank of England[0] or the US Dept of Treasury Bureau of Engraving and Printing[1].
In the absence of a Central Bank of Kong to perform this function, the Kong people could make their new physical currency more robust by putting their fancy chips and whatnot inside some discs made of a metal that was resistant to corrosion and oxidation and had a very high melting point. Perhaps also using a rare metal with high economic value, preferably with a standardized weight and purity, so it could also better act as a store of value and be more difficult to counterfeit. At that point you could also take out the fancy chips and whatnot in order to improve reliablility, usability etc.
[0] https://www.bankofengland.co.uk/banknotes/damaged-and-contam...