Important is pronounced not with two hard t sounds, but with a glottal stop: Impor[glottal stop]ant. That's not laziness, that's my actual dialect of English spoken by actual adult people.
Reference video: https://www.youtube.com/watch?v=_GfTa7ozjYc
I agree with others here too. At the moment the voice sounds like "grinning barbie" from the end of Toy Story 2. Just stop smiling constantly and talk like a real person chatGPT!