Renew the key pair you intend to use with Eddie (or renew them all to be on the safe side for the future) in the client area, then restart Eddie and try again. The "problem" is that SHA1 is considered a weak digest in OpenSSL 3. Even if new and renewed client certificates have been signed with SHA512 for years now, the CA cert from AirVPN was still SHA1-signed. This threw the error for users of Schwabe's OpenVPN for Android and throws it for you now, too: If in a given certificate chain there is