GetPlayerCombinedInfo() => result.InfoResultPayload.AccountInfo.FacebookInfo is null but
GetUserCombinedInfo() => result.AccountInfo.FacebookInfo contains data for linked accounts
When you query for your own PlayFab ID (by not specifying that in a call to either), all data is returned. The GetPlayerCombinedInfo API call has a bug where it's not checking that the PlayFab ID specified is your own, if you include a specific PlayFab ID. We'll have that fixed shortly, but in the meantime all you need to do is leave the PlayFab ID out of the call.
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