If one prays with a miswak in his mouth while forgetting it, is his prayer invalid?

Question:
May Allah reward you, Honorable Shaykh. This questioner says: If a person goes to the mosque with a miswak in his mouth, then begins the prayer with the miswak still in his mouth, and after one rak'ah he finds the miswak in his mouth and is taking it out, is this prayer or that rak'ah invalid?

Answer:
No, the rak'ah is not invalid because of the miswak in his mouth, as long as he recited al-Fatihah and performed the pillars and obligations, his prayer is not invalid because of the miswak.