If he is interrupted when reading Qur’an, does he have to repeat the isti‘aadah when wants to resume?
Question

I would like to know that whilst reciting the quran from the mushaf if a person gets interrupted by a family member then should they read aoozobillah again or can they just carry on reciting the quran
Praise be to Allah.If someone interrupts his reading or recitation of Qur’an for a valid reason, such as sneezing, or returning the greeting of salaam, or answering a question, and the like, and he intends to complete his reading once the excuse is no longer there, then the first isti‘aadhah (“A‘oodhu Billahi min ash-shaytaan ir-rajeem (I seek refuge with Allah from the accursed shaytaan)”) is sufficient, and he does not have to repeat it, unless the interruption goes on for a long time, in which case he should repeat it.
Ibn al-Muflih said in al-Aadaab ash-Shar‘iyyah (2/326):
It is Sunnah to seek refuge with Allah (by saying “A‘oodhu Billahi min ash-shaytaan ir-rajeem (I seek refuge with Allah from the accursed shaytaan)”) when starting to read or recite Qur’an.
But if he stops reading with the intention of not resuming, he should repeat the isti‘aadhah when he comes back to it.
If he is interrupted by an excuse, and has resolved to complete it when the excuse is no longer there, then the first isti‘aadhah is sufficient. End quote.
Ar-Ruhaybaani said in Mataalib Ooli an-Nuha fi Sharh Ghaayat al-Muntaha (1/599):
If he stops reading with the intention of not resuming, then he wants to go back to it, he should repeat the isti‘aadhah.
If he interrupts it for an excuse, and has resolved to complete it when the excuse is no longer there, such as taking something or giving something, or answering a questioner, or sneezing, and so on, then he does not have to repeat the isti‘aadhah, because he is continuing his reading. End quote.
This applies if the interruption is not lengthy. But if the interruption is lengthy, then it is Sunnah for him to repeat the isti‘aadhah.
Az-Zarkashi (may Allah have mercy on him) said:
It is recommended (mustahabb) to seek refuge with Allah (isti‘aadhah) before starting to recite, then if he stops reading with the intention of not resuming then later on he wants to resume, he should repeat the isti‘aadhah.
If he interrupts it for an excuse and has resolved to go back to it, the first isti‘aadhah is sufficient, so long as the interruption is not lengthy." (Al-Burhaan fi ‘Uloom al-Qur’an  1/460).
An-Nawawi (may Allah have mercy on him) said in al-Majmoo‘ (3/281):
One isti‘aadhah is sufficient, so long as he did not interrupt his recitation by speaking or remaining silent for a long time.
If he interrupts it with one of these two, then he should repeat the isti‘aadhah.
If he does the prostration of recitation then carries on reading or reciting, he does not need to repeat the isti‘aadhah, because this is not an interruption, or it is only a brief interruption. This was stated by al-Mutawalli. End quote.
But if he interrupted it for a reason having to do with his reading, such as asking a question or seeking an explanation of the verses that he is reading and the like, he does not have to repeat the isti‘aadhah. Ibn al-Jazari said in an-Nashr (1/259):
If the reader interrupts his reading for a reason, such as pausing to offer a supplication, or to say something that has to do with what he is reading, he does not have to repeat the isti‘aadhah. End quote.
If he repeats the isti‘aadhah after interrupting his reading by saying something that has nothing to do with the recitation – such as greeting someone with salaam – that is good.
An-Nawawi said in at-Tibyaan (p. 124):
If he is reciting whilst walking, and passes by some people, it is recommended (mustahabb) to interrupt his recitation and treat them with salaam, then go back to his recitation. And if he repeats the isti‘aadhah, that is good. End quote.
And Allah knows best.