There is punishment in grave.Following hadith proves it.
حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا جَرِيرٌ، عَنْ مَنْصُورٍ، عَنْ أَبِي وَائِلٍ، عَنْ مَسْرُوقٍ، عَنْ عَائِشَةَ، قَالَتْ دَخَلَتْ عَلَىَّ عَجُوزَانِ مِنْ عُجُزِ يَهُودِ الْمَدِينَةِ فَقَالَتَا لِي إِنَّ أَهْلَ الْقُبُورِ يُعَذَّبُونَ فِي قُبُورِهِمْ، فَكَذَّبْتُهُمَا، وَلَمْ أُنْعِمْ أَنْ أُصَدِّقَهُمَا، فَخَرَجَتَا وَدَخَلَ عَلَىَّ النَّبِيُّ صلى الله عليه وسلم فَقُلْتُ لَهُ يَا رَسُولَ اللَّهِ إِنَّ عَجُوزَيْنِ وَذَكَرْتُ لَهُ، فَقَالَ
صَدَقَتَا، إِنَّهُمْ يُعَذَّبُونَ عَذَابًا تَسْمَعُهُ الْبَهَائِمُ كُلُّهَا "
فَمَا رَأَيْتُهُ بَعْدُ فِي صَلاَةٍ إِلاَّ تَعَوَّذَ مِنْ عَذَابِ الْقَبْرِ
Narrated `Aisha:
Two old ladies from among the Jewish ladies entered upon me and said'
"The dead are punished in their graves," but I thought they were telling a lie and did not believe them in the beginning. When they went away and the Prophet (ﷺ) entered upon me, I said,
"O Allah's Messenger (ﷺ)! Two old ladies.." and told him the whole story. He said, "They told the truth; the dead are really punished, to the extent that all the animals hear (the sound resulting from) their punishment."
Since then I always saw him seeking refuge with Allah from the punishment of the grave in his prayers.
Sahih al-Bukhari 6366
In-book : Book 80, Hadith 63
USC-MSA web (English) : Vol. 8, Book 75, Hadith 377 (deprecated)
Believe in punishment in grave, Qabr Mein Azab, Don't deny punishment in grave.