I'm getting a dialogue that says "Invalid key hash" and can't transfer my data.
Regarding your concern, the error "Invalid key hash" may occur due to the following reasons:
- Interference with a Facebook account you are logged into
- Information has been incorrectly acquired from an unauthorized application
If your account was registered before the application was available in a specific country, then the app may have been acquired through unofficial channels.
Aforementioned cases are not subject to support.