IPSec Tunnel Will Not Come Up with Tunneled traffic dropped due to Encapsulation Error

• IPSec Tunnel will not come up and tunneled traffic is being dropped due to encapsulation error
• Phase1 is failing
• There are no IKE/ISAKMP packets initiated by the firewall towards peer
• Global Counters shows encapsulation error as shown below while filtering for tunneled traffic

flow_tunnel_encap_err     1      1 drop     flow    tunnel    Packet dropped: tunnel encapsulation error

• Testing vpn gateway from cli returns message "SA test initiate ignored: cannot find tunnel configuration." in ikemgr.log as shown example below

> test vpn ike-sa gateway <GATEWAY>
<DATE>  [INFO]: {    3:     }: <GATEWAY>: IKEv2 SA test initiate ignored: cannot find tunnel configuration

• Flow basic debug shows interesting packet dropped due to tunnel resolution failure

Packet enters tunnel encap stage, tunnel interface null
Resolving tunnels in multi-tunnel case for ifp:tunnel.x   <--------  x is the associated tunnel interface
Packet dropped, tunnel resolution failure

• Next Generation Firewall
• PAN-OS 10.1.5, 10.1.6 
• IPSec configured and terminating on another Next Generation Firewall

admin@firewall(active)> configure
admin@firewall(active)# show network tunnel ipsec ShapeTX_AWS_Tunnel
  tunnel-interface tunnel.1;
  disabled yes;                                        <-------------------- DISABLED
  comment "Left IPSEC tunnel to AWS";

1. From Network > IPSec Tunnels >  select the IPSec Tunnel configuration 

2. Select Enable 

3. Commit Changes

> configure
Entering configuration mode
# set network tunnel ipsec <Name of IPSec Tunnel> disabled no
# commit