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falling behind (with a payment); being in arrears; non-payment; default; delinquency
税金の怠納が続くと財産が差し押さえられる。
If tax delinquency continues, assets may be seized.
怠納者に対して督促状が送付された。
A demand notice was sent to those in arrears.
保険料の怠納により給付が停止されてしまった。
Benefits were suspended due to non-payment of insurance premiums.