Describe the problem:
Unknown file. Needs mapping
Which exchange/wallet is this regarding?
Talisman
How did you import data into this wallet?
Csv file
What have you tried to fix this so far?
Nothing
Hey @graphenes 
Thanks for your message. 
Talisman is a multi-chain wallet, like MetaMask, so you should be able to find your Polkadot address within the wallet (see here), then use that to add your transactions to Koinly:
https://koinly.io/integrations/polkadot/
Note that Koinly doesn’t yet support substrate addresses from Polkadot (addresses that start with a ‘5’), so if you find yours is one of these, you can covert it to a workable address here - https://ss58.org/
I hope that helps! 