Macbook can´t connect to Cisco IPSec server [solved]

Hey,

i´m still a bloody rooky with Mikrotik.
I´m trying to connect from my Macbook´s system VPN via my own hAP ax³ to a Cisco IPSec server.
But i´m always getting

The negotiation with the VPN server failed. Verify the server address and try reconnecting.

If i just switch to mobile network the VPN connection starts immediately.

Also if i use L2TP over IPSec from the Macbook i immediately get a running connection without switching to mobile network.

Can someone give me a hint or maybe help me to figure out why Cisco IPSec connections can´t be connected

Best
Tim