Is it considered disbelief to sleep through the Fajr prayer after waking up at its appointed time, and being unable to perform it at the designated time due to obsessive thoughts about ablution, or preoccupation with another condition, or insufficient time, knowing that one is diligent in performing prayers in the mosque, and the intention when sleeping through the prayer is unclear?

Prayer holds immense significance in Islam, being the second pillar after the two testimonies of faith, and it must be preserved. It is permissible to sleep before the prayer time begins, even if one suspects missing it, because it is not obligatory at that moment. However, regarding sleeping after the time has entered, if the questioner knows that they will wake up for it, there is no sin upon them. But if they know that sleep will consume the entire prayer time, then they are sinful and must repent. The missed Fajr prayer must be made up. What the questioner experienced does not amount to disbelief.