If the statistics on your Cisco VPN client are showing a value for sending, but 0 for receiving,and Decrypted has a value of 0, this is a sign of IP Fragmentation.
To resolve, please adjust the MTU buffer Size of the packets.
Go to "C:\Program Files (x86)\Cisco Systems\VPN Client\SetMTU.exe"
Choose respective adapter (Cisco Adapter is usually Local Area Connection 2 but not always. You can verify in network and sharing center under "Change Adapter Settings" or CMD>control netconnections) MTU Options>Custom> edit value to 1208
https://www.cisco.com/c/en/us/support/docs/ip/generic-routing-encapsulation-gre/25885-pmtud-ipfrag.html#anc2