A key is meant for a single trader. It works across several of your own devices, but concurrent access is limited — this protects against sharing the key with others.
Linked devices are visible in your dashboard. If you changed computers and hit the device limit, close the terminal on the old computer and unlink it in the dashboard with the “Unlink” button (up to 3 times per 30 days on your own), or message support and we’ll help. If concurrent use is detected, the indicator shows a warning right on the chart.