i have the seed...but the transaction completed...Eletrum turned off their servers during the transaction.
Assuming this is correct, your funds are safe. Just keep the seed!
"Until then, your wallet is not lost and you can restore it from its seed using an up-to-date version of Electrum outside of Tails."
If you don't want to use anything other than Tails, waiting for a newer version seems to be the easiest right now. You can of course export your private keys and switch to a different wallet, but I don't recommend doing that if you're not absolutely sure what you're doing.
if the transaction completed...how do i get back what was deemed a successful transaction?
Install the latest version of
Electrum from the official website (and nowhere else!), import your seed, and your funds should show up again.