He was asked:

“Regarding someone who recites the Quran but has no one to ask about errors in recitation and the like: if he gets stuck on something and consults a copy of the Quran, does he incur any sin?”

He answered:

If he needs to recite the Quran, he should recite it to the best of his ability and consult a copy of the Quran wherever he encounters difficulty. “Allah does not burden a soul beyond its capacity.” He should not abandon the recitation he needs and brings to completion because of occasional mistakes, provided it does not entail an overriding harm. And Allah knows best.

He was asked:

“What if someone pronounces a word in the accusative instead of the genitive during his prayer?”

He answered:

If he does so knowingly, his prayer is invalid, because he is treating his prayer frivolously. If he does so out of ignorance, his prayer is not invalid according to one of the two views.