Problems with e-Cash ?

https://www.thetimes.co.uk/article/sweden-nation-that-pioneered-living-without-cash-warns-hoard-your-banknotes-6f72jqbf3

Sweden, nation that pioneered living without cash, warns: Hoard your banknotes
As Britain edges towards a cashless future, Sweden has urged its citizens to stockpile change in case of power cuts, a cyber-attack or war

Everyone in Sweden has been urged to stockpile coins and banknotes in case the country’s move towards a cashless society leaves them without money in a cyber-crisis. In a move that will sound alarm bells in the UK, Sweden — one of the most advanced nations for digital payments — has warned that its people could be unable to buy anything if its computer networks were put out of action.

The Swedish Civil Contingencies Agency, an arm of the government, has sent guidance to every home telling residents to squirrel away “cash in small denominations” in case of emergencies ranging from power cuts or technology glitches to terrorism, cyber-attacks by a rogue government or war.