In order to connect Leadifly to Sendlane, please make sure that you have followed these steps:
1. Copy your 'API key', 'Hash Key' and 'Domain' from Sendlane and paste them into the fields under the Sendlane tab in Leadifly. These can be found under 'Account Settings' on the right.
2. Click 'save changes'.
3. After you save your new credentials, you may also need to click the Validate Settings button, if it is visible.
4. In order to use Sendlane, check the box which says 'Use Sendlane'.