Error after sharing

Hello folks,

Here is the issue I’m having with the plugin for the moment. When I share a post on social media, I get the thanks and Invitation to Follow window. No matter which of the buttons I click on -Pinterest, Facebook, Twitter- I get this error message:

{"errors":[{"code":"120","source":{"pointer":"/data/attributes/username"},"detail":"Invalid username, app_id or app_id_name. Check out the docs at https://github.com/shareaholic/shareaholic-api-docs/blob/master/api_follow_api.md for usage examples."}]}

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