No, you don't have to ask permission to use Leadinfo.
Permission is not always required under the GDPR. Another basis of the GTC is the "own justified interest" (Article 6(f) of the GTC). In doing so, you may work with personal data without permission, provided this serves a clear interest and you take privacy into account. Marketing and analytics are considered a clear legitimate interest, and Leadinfo uses personal data only to a very limited extent. This takes adequate account of privacy.