Can a person be excused for not praying because he is unaware that it is obligatory?

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Check below answers in case you are looking for other related questions:
Who are the ones who will be excused for ignorance about ‘aqeedah and matters of fiqh?
Ruling on marriage contract with one who was not praying then Allaah guided him

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Is it permissible for them to use their father’s money when he does not pray?
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Praying 'Ishaa' the next morning
Who are the ones who will be excused for ignorance about ‘aqeedah and matters of fiqh?
Ruling on marriage contract with one who was not praying then Allaah guided him

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