Same problem with FG60E, firmware V6.2.2, Android V9 (Samsung Galaxy Note8), latest update to Android Forticlient V6.2.2.0312 has broken the ability to use VPN. It worked properly with the earlier Android Forticlient.
VPN works fine from Windows laptop with Forticlient 6.0.6.0242
When attempting to connect from Android, the VPN event log shows "progress IPsec phase 1" as "negotiate" "success", then shortly afterwards "delete IPsec Phase1 SA" as "IPsec Phase1 SA deleted".
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