Adjust/personalize auto-correction on Android
Add the word to your personal dictionary.If you are using Gboard:


Go to its settings then Dictionary.
Click on Personal dictionary
Select a language or All languages if you want to add the word for every language.
Click the + button.
On "Type a word", enter ie.. Press the arrow to go back to the previous screen. (You can enter a shortcut for the word if you want but with your word being so short I don't think it is necessary).


For now on ie. will appear when you type and will not be auto-corrected.