If you see the clip of him speaking to it (he's using voice chat on his phone and recording with another phone), it counts the 3rd 'e' as the 3rd 'e' twice. It doesn't skip it, it just doesn't process two 'e's adjacent as separate.
I saw the same glitch previously when someone asked it to count the 'r's in "strawberry". It just doesn't properly process the repeat letter.
I would have liked to see him ask for the number of letters in ‘seventeen’ which would be 9, and then ask the AI to identify each of those letters individually and give the number of each of the different letters to match the total.