Migration from Exchange 2010 to 2013 - Relinquished Error

Hi every one, 

I am running into some problems when migrating mailboxes from exchange 2010 to 2013

for some of them when i ask with Get-MoveRequestStatisctics, i get those StatusDetail

Relinquished
and
RelinquishedMDBfailover

and i can't find any explanations
Can anybody help me ?

Thanks