Недоимка указана в личном кабинете налогоплательщика.

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Breakdown of Недоимка указана в личном кабинете налогоплательщика.

• указать: to indicate
• личный кабинет налогоплательщика: the taxpayer's online account
• недоимка: the tax arrears

Questions & Answers about Недоимка указана в личном кабинете налогоплательщика.

Why is указана feminine, and not указан or указано?

Because it agrees with недоимка, which is a feminine singular noun.

• недоимка = feminine singular
• so the short-form participle must also be feminine singular: указана

Compare:

• долг указан — долг is masculine
• сумма указана — сумма is feminine
• значение указано — значение is neuter

So in this sentence, указана matches недоимка.

What exactly is указана grammatically?

Указана is the short form of a passive past participle from the verb указать.

In this sentence, it means something like:

• is indicated
• is stated
• is listed
• is shown

So Недоимка указана... literally means The arrears/underpayment is indicated/listed...

This short-form participle is very common in official and written Russian, especially in bureaucratic, legal, and technical language.

Why is it в личном кабинете, not в личный кабинет?