If you want to backup your account data and store it locally please go to the "Enter Coins" page and choose Export - CSV. For a recovery you can use the CSV Importer.
Exchange API imports seemingly won't re-import transactions even if you rename the Exchange/Group fields in the data, or delete/use a new API key.
The only way to get them to re-import seems to be to entirely delete the data for that exchange, then import it again.
Suggest making a backup of trades in CoinTracking first, as well as exporting a CSV of all of your trade data (to manually copy comments/etc over again afterwards)
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