While attempting to connect, try taking a packet capture on the WAN interface of the MX (Network-Wide > Packet Capture) and confirm that traffic from the public IP of your client computer is reaching the MX. If it doesn't it would indicate an issue upstream or on the client device. This KB article also gives some great troubleshooting steps: https://documentation.meraki.com/MX/Client_VPN/Guided_Client_VPN_Troubleshooting
... View more