Th differ if Salat At-Tasbeeh is a recommended sunnah act to practice. The scholars differ over the status of the hadith some say it’s fabricated, others say its Da’eef, Hasan or Sahih.

Narrated Abdullah Ibn Abbas: The Messenger of Allah (ﷺ) said to al-Abbas ibn Abdul Muttalib: Abbas, my uncle, shall I not give you, shall I not present to you, shall I not donate to you, shall I not produce for you ten things? If you act upon them, Allah will forgive you your sins, first and last, old and new, involuntary and voluntary, small and great, secret and public.

These are the ten things: you should pray four rak’ahs, reciting in each one Fatiha al-Kitab and a surah. When you finish the recitation of the first rak’ah you should say fifteen times while standing: “Glory be to Allah”, “Praise be to Allah”, “There is no god but Allah”, “Allah is most great”. Then you should bow and say it ten times while bowing. Then you should raise your head after bowing and say it ten times. Then you should kneel down in prostration and say it ten times while prostrating yourself. Then you should raise your head after prostration and say it ten times. Then you should prostrate yourself and say it ten times. Then you should raise your head after prostrating and say it ten times in every rak’ah. You should do that in four rak’ahs.

If you can observe it once daily, do so; if not, then once a week ; if not, then once a month; if not, then once a year; if not, then at least once in your lifetime.

Recorded in Sunan Abu Dawud (no. 1297) and Sunan Ibn Majah (no. 1387)

Shaykh al-Islam Ibn Taymiyah (رحمه الله) said:

The best of the reports narrated about these prayers is the narration about Salat al-Tasbeeh, which was narrated by Abu Dawud and al-Tirmidhi, but nevertheless none of the four imams spoke of it; in fact, Ahmad regarded the narration as da‘eef (weak), and these prayers are not mustahabb (recommended).

See Majmoo‘ al-Fatawa (11/579)

Imam ibn Qudamah (رحمه الله) said:_

_With regard to Salat al-Tasbeeh, Ahmad said: I do not like it. It was said to him: Why? He said: There is nothing Sahih about it, and he waved his hand as if dismissing it.

See Al-Mughni (1/438)

Imam Al-Nawawi (رحمه الله) said: Al-Qadi Husayn, and the authors of al-Tahdheeb and al-Tatimmah said: Salat al-Tasbeeh is mustahabb, because of the hadith narrated concerning it. But this view of it as mustahabb is subject to further discussion, because the hadith in question is da‘eef, and it involves changing the regular format of the prayer, so it should not be done without a hadith (to support it).

Al-Tirmidhi said: More than one hadith was narrated from the Prophet (ﷺ) concerning Salat al-Tasbeeh, but not many of them are saheeh. And al-‘Aqeeli said: There is no proven hadith about Salat al-Tasbeeh. See Majmoo‘ Sharh al-Muhadhdhab (3/547-548)]

Summarised from the answer of Shaykh Abdul Aziz bin Marzouq At-Tarefe: Salah At-Tasbeeh is not authentically established, the narration was rejected by Imams like Imam Ahmad, Imam Abu Haatim and Shaykhul Islam ibn Taymiyyah. There many defects in the text. This prayer was never performed by the Prophet (ﷺ), nor is it reported that any of his companions or the Tabi'een (in general) performed it, it was mentioned by some Imams like that which is reported about ibn Mubarak that he done it.