Assalamalikum,my doubt is regarding the missed fasts.I wanted to keep my missed fasts so i made intention that i will fast five days continuously,but due to some reason i cudnt fast 2 days in between nd for my fast next day,my niyah was something like this "if i am able to wake up for fajr than i will fast" but with Allah's grace i woke up for fajr nd when i was praying fajr in my heart i again made niyah to start fasting.my question is ,is my fast valid?

All perfect praise be to Allaah, the Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.

In the obligatory fasting, like fasting Ramadan or making up for the obligatory fasting or fasting for expiation, one has to have the intention to fast from the night before. Besides, this intention has to be absolutely certain. Therefore, your intention that is conditioned upon waking up for Fajr is not sufficient for you because it is not an intention that is absolutely certain. Also, having the intention to fast after the beginning of Fajr is not sufficient for obligatory fasting as we have already mentioned.

Therefore, you will be rewarded for fasting these two days, but they will be considered as voluntary fasting as this is not sufficient for making up the obligatory fasting (which you are obliged to fast).

Allaah Knows best.