[Hope]

Thank you for your honesty because your Quran did not mention the prophecy of prophet Isaiah at all.....

Muslims have been going to the Bible to look for evidences to justify Muhammad especially from the verses of Isaiah... because in your Quran Jesus said

And ˹remember˺ when Jesus, son of Mary, said, “O children of Israel! I am truly Allah’s messenger to you, confirming the Torah which came before me, and giving good news of a messenger after me whose name will be Aḥmad.”1 Yet when the Prophet came to them with clear proofs, they said, “This is pure magic.”

We don’t have to see evidence in your bible to confirm prophet Muhammad.
Our scholars are trying to educate you with your scripture.

John chapter 14 verse 16:
"And I will pray the Father, and he shall give you another Comforter, that he may abide with you forever."

Gospel of John chapter 15 verse 26:
"But when the Comforter is come, whom I will send unto you from the Father, even the Spirit of truth, which  
proceedeth from the Father, he shall testify of me."

Gospel of John chapter 16 verse 7:
"Nevertheless I tell you the truth; it is expedient for you that I go away: for if I go not away, the Comforter will not come unto you; but if I depart, I will send him unto you".