The key is checked against the server, so a key with a typo simply changes nothing. Copy it again from your dashboard rather than retyping it, and paste it into the plugin under Account. A key looks like VX-XXXX-XXXX-XXXX and works on up to three Figma accounts.
When the plugin does not know the key
Under Account, beneath the key, the plugin then says: “We don’t know this key, so you are on Free for now.” Free keeps working in the meantime: you can export as usual. Paste the key again from the mail you got at checkout, or write to info@videoexportify.com.
Try it on your own frame
Free to try, no account. Or watch the plugin work in the browser first.