If a wife neglects her husband unintentionally during Ramadan and he isn't pleased with what she does, e.g. spends more time in reading Qur'an and performing prayers and making Du’a during the night, will Allah still accept her prayers and Du’a?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

If by performing optional prayers you harm your husband, then it is permissible for him to prevent you from that because you are making him lose the right of enjoying you.

The wife is not permitted to do what prevents this enjoyment as this is a right confirmed by the marriage contract. Fulfilling the terms of the contract is given priority over performing the Sunan (plural of Sunnah) and Nafl (supererogatory) actions.

Al Baji said in his book Al Muntaqi while speaking about fulfilling the vow about a prayer, etc: “If that causes harm to her husband, then he can prevent her from it, because he has the right to take pleasure in her, and she is not allowed to do anything that will prevent that.”

So, if this is the case regarding fulfilling the vow, then what is not a vow is more appropriate. 

As regards the ruling on the prayer, it is valid. But you are sinful in not obeying the order of your husband, as you neglected his right without any reason.

As for the acceptance of the prayer, i.e. the reward, then this is a matter that only Allaah Knows.

It is reported in a Hadeeth that the Prophet said: “There are three kinds of people whose prayers are not lifted more than a span of a hand from their heads; a person who leads the people in prayer while they are objecting to him leading the prayer, a woman who spends the night while her husband is angry about her …..” [Ibn Majaah and others]

Al Munaawi said while explaining the saying of the Prophet : “While her husband is angry about her.”: “It is because of her bad character, or by her losing one of her husband’s rights which should be fulfilled by her towards him as an obligation or as something desirable].

Therefore, you have to apologize to your husband and seek his pleasure.

Allaah Knows best.