Yes. Ahl al-Sunnah affirm both the punishment and the blessing of the grave as a matter of the unseen established by the Qur'an and by widely transmitted narrations: after burial a person is questioned about his Lord, his religion and his Prophet, and the grave becomes either a garden or a pit until the Resurrection. Allah says of Pharaoh's people, "The Fire, they are exposed to it morning and evening" (40:46), and of Nuh's people that after being drowned "they were made to enter a Fire" (71:25) — both before the Hour has come. The Prophet ﷺ passed by two graves and informed his Companions that their occupants were being punished, one for not guarding himself from urine and the other for carrying tales, and he taught the ummah to seek refuge from the punishment of the grave in every prayer. We affirm it without asking how, and we do not judge it by the state of the body, since the barzakh has its own reality; the protection from it is sincere faith and righteous deeds, for Allah "keeps firm those who believe with the firm word" (14:27).
Q&A · Belief
Is the punishment of the grave real?
Evidence — the daleel
Quran 40:46Quran 71:25Quran 14:27Sahih al-Bukhari and Sahih Muslim — hadith of Ibn 'Abbas on the two graves whose occupants were being punished, one for not guarding against urine and the other for namimahSahih al-Bukhari and Sahih Muslim — hadith of Abu Hurayrah on seeking refuge from the punishment of the grave in the tashahhud
On deen2u
Informational, not a personal fatwa. Consult a qualified scholar for rulings on your situation.