What should a person who joined the prayer late do, if the imam made a mistake and said the tasleem after the third rak‘ah of a four-rak‘ah prayer, then remembered and stood up to do a fourth rak‘ah?

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Check below answers in case you are looking for other related questions:
Should one who joined the prayer late repeat the prostration of forgetfulness if he did it with the imam?
What to say in sujood al-sahw

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Related Answers:
Sujood Ul-Sahw if in doubt while praying
What should be said in the two prostrations of forgetfulness and in between them?
Imam errs during prayer and does not know what is the mistake
Should one who joined the prayer late repeat the prostration of forgetfulness if he did it with the imam?
What to say in sujood al-sahw

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