A recipient can only receive files from a single deleted user at a time. If you've deleted several team members and transferred their files to a single user within a short period, then the file transfer may fail temporarily. You should be notified via email if a transfer fails, at which point you can attempt the transfer again.   To prevent file transfer failures, it's best to request a single account transfer, wait a few minutes, and then request the next transfer for the next account, and so on until all of the files or accounts are transferred.   Alternatively, the admin or the previous file owner can share individual files or folders as needed.