Waswasas and stray thoughts

Few years before I have uttered some blasphemous words for Allah because of my compulsive waswasah. I was combating with Shaitaan in my mind and whatever Shaitaan puts in my heart I directly says to Shaitaan verbally. So one day my tongue slipped and unintentionally whatever waswasas I had came on my tongue. I have heard that all this is from Shaitaan and I need to reject and ignore these waswasas. My question is were my all past good deeds gone? Because I watched one video of a mufti, he said one who uttered kufriya kalimaat would be gone beyond the pale of Islam.