"No, it is there."
The comma makes all the difference I think. That is what it would mean without the comma.
(Just to complicate things Duo ignores most punctuation so I tried 不在那儿 without the comma and it was accepted, but it is really not correct for this sentence without the comma as I understand it, since the comma completely changes the meaning.)
On a MAC, I have setup 'PINYIN - simplified' as a alternate keyboard choice. I can quickly switch between English and Pinyin. I can wait for the individual character selection choice to show up or just keep typing. When you just keep typing it does predictive fill in. Most of the time it comes out correctly. You should be able to setup alternate keyboards on your computer and phone. On the computer it will be in the 'key board' settings and then 'input sources'. On a phone look for the keyboard settings, then you should be able to select alternate keyboards.
I would like my Chinese to be as good as your English. Yes I know your meaning, they are different words. I was commenting on the auto type function. It automatically changes the characters from 那儿 to 哪儿， sometimes. Thanks for your comments. We appreciate native Chinese speakers helping us understand.