The Quran teacher at the school where I used to teach told me about this information regarding Asr namaz. And I also found this hadith:
‘Whoever does not pray ‘Asr, his good deeds will be annulled.’ (Bukhaari)
**Buraidahu (Radhiallaho anha) reported: The Messenger of Allah (Sallallaahu ‘alaihi wasallam) said, "He who misses the `Asr Salat (deliberately), his deeds will be rendered nul and void.’’
[Al-Bukhari].
Commentary: It is a serious sin to miss any of the prescribed Salat deliberately. Some people regard it even an act of Kufr. But the willful omission of `Asr prayer is one of the most serious sins. Its omission nullifies one’s good deeds. Observing this Salat is, therefore, highly essential.
Riyad-us-Saliheen – Hadeeth No.1052.**