'Aishah (May Allah be pleased with her) reported:
If the Messenger of Allah (ﷺ) missed his night (Tahajjud) Salat because of indisposition or the like, he would perform twelve Rak'ah during the day.[Muslim]. (DE)
App reference (DE): Book 9, Hadith 191 (DE)
Arabic/English book reference (DE): Book 9, Hadith 1181 (DE)