iTunes always reset the "Automatically Back Up" option to "This Computer"

So, this section of iTunes idevice option always keeps resetting to "This Computer" from "iCloud", whenever the sync finishes / the device is reconnected.

Is there any guess why this is happening, even though iCloud Backup is turned on in my idevice's settings? Any solution I can try to do?

Solved - it seems that this error happens when you restore your idevice from icloud backup.

Go to idevice's settings>iCloud>Backup and disable and reenable iCloud Backup, and iTunes will now remember this settings.

tl;dr: it didn't have something to do with iTunes, the idevice was the problem.

So now one last thing ...if this one fails too ,,then its only Apple Support. Connect your iPad to iTunes. Back it up (check the Encrypted Backup box). When local iTunes backup is made, disconnect the iPad. Leave your iTunes app on At your 🖥. Then with power on, at your iPad, make an iCloud backup. Check itunes app iCloud or iTunes (encrypted) backup is checked?? The (at all cases) sign out of iTunes account & resign in. Reboot 🖥 & iPad at the end of all the procedure. If those workarounds don’t work ..contact Apple Support. 🤔