Sunan Ibn Majah
1781
Daif+3

It was narrated from Ibn ‘Abbas that:The Messenger of Allah (ﷺ) said concerning the person observing I’tikaf. “He is refraining from sin and he will be given a reward like that of one who does all kinds of good deeds.”

DaifAl-Albani
DaifMuhammad Fouad Abd al-Baqi