I tried with both a PC and Android phone, with the same results.
I don't know how to properly create the certificate.
Here is what I did:
I went to Security»Authentication»Internal User Database»Groups and Users add an group and user for openvpn
I did the following in the OpenVPN settings
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In "remote network I have no idea what I should put there, as there's no constant network from which I will be connecting, I'm connecting from the internet and not some known local network.
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In OpenVPN app I entered my DDNS address, I tried with and without specifying the port number
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I received an error: "Faild to import profile - Host is unreachable"
I tried to go to the VPN>>OpenVPN>>omni Ssl Configuration, and tried to add and download new client configuration file (ovpn), and load it to the OpenVPN phone app, and I received the error: "Failed to parse profile: option_error: remote option not specified"