iPhone keyboard text replacements lost I recently upgraded an iPhone from iOS 9.3 to iOS 11.1.
Then I had to upgrade all the installed applications (about 60).
A few weeks later, when I needed to write m² I typed my old defined shortcut which is: m ^2. It failed i.e. I got exactly what I typed: m ^2.
I opened Settings &gt; General &gt; Keyboard &gt; Text Replacement and discovered it is completly empty. From memory I had defined about 50 of these practical shortcuts.
Other technical details in relation with long discussions on this topic:

this iPhone isn't jail broken,
this iPhone isn't saving anything on iCloud,
I only sync from my Mac toward my iPhone (Contacts, Calendars, Music).


Update 27/08/2018
The same problem detected without any upgrade (I am still on iOS 11.1)
but after an activation of iCloud.


Did anyone experience the same problem?
Does anyone have a hint of where might be the origin of this bug?
I might just guess why you have this problem. iCloud Core Data was used before CloudKit and it was absolutely unreliable for syncing among your devices. Shortcuts you created on iPad did not appear to be on you iPhone. From iOS 11 I suppose they started using CloudKit that is very efficient with syncing all your data. So you could just create all your shortcuts once again knowing it should be the last time you do so