Some people using the new iOS 11 have been encountering a strange issue where their predictive text.
It seems that some users are seeing “A[?]” as the first word that is recommended when using the default iOS keyboard, and so when the letter “I” is typed, it gets autocorrected to A[?].You can see the example below.
Right now it’s not clear why this bug is happening. It could be related to the new emoji was added in iOS 11.
There is a workaround. Apple is recommended that if you are affected to use text replacement.
The way you can do this is by: Go to Settings > General > Keyboard > Text Replacement. Type in an uppercase "I" for the phrase, and a lowercase "i" as the replacement.