l2tp/ipsec vpn setup

I am trying to setup a l2tp/IPsec vpn for new Mac users. I have it setup, however I’m getting a failed to pre-process ph2 packet in logs. I have removed the default group policy from IPsec peer. However, I still get the error. Any ideas? Thanks!

Post your config export from /ip ipsec and /ip firewall filter here so we can have look at it.
-Chris