Ok after efforts of many days I have found a work around and resolved the issue now my account is syncing.
First Uninstall previous SwiftKey keyboard, then download and install any old version app from Google and and sync your account then update the app from playstore. In my case I installed SwiftKey version 7.0.9.28.
I have same problem
Recently i have changed my mobile but SwiftKey not predicting my saved words
Same problem personalized dictionary backup is not working.
Yeah. Changed my phone. Words are not syncing
Same issue here after upgrading to a new phone.
Same problem here
Ok after efforts of many days I have found a work around and resolved the issue now my account is syncing.
First Uninstall previous SwiftKey keyboard, then download and install any old version app from Google and and sync your account then update the app from playstore. In my case I installed SwiftKey version 7.0.9.28.