Here are some issues related to MAC-OS- https://docs.aws.amazon.com/vpn/latest/clientvpn-user/macos-troubleshooting.html
Refer them for accurate troubleshooting. Also, to know in detail, your VPN client logs might help. If possible, please provide those or raise a case with AWS support and get those checked.
I would also recommend you to try Open VPN client and see if that is giving you the same errors that AWS Client is been giving to rule out any issues with the AWS Client.
The AWS VPN Client OVPN profile isn't compatible with OpenVPN, as it has some AWS-specific settings, baked into the binary, that break OpenVPN client (like auth-federate, which OpenVPN has no plans to make compatible).
I'll try reaching out to AWS support.
Yes. Please provide the logs to them as mentioned above in the link along with the configuration.
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