Site2Site VPN and IKEv2 VPN - No Route to Remote Site

Hello,

I have a problem with my ATP.

There are 2 different VPNs:

• Site2Site (HQ<->EXT): 172.16.0.0/16 (HQ) to 172.17.0.0/16 (External Site)
• IKEv2 for clients (HQ): Range 192.168.10.10 to 192.168.10.100

The S2S connection to the external site (EXT) works without problems when I use it in the HQ, i.e. without an additional VPN.

The IKEv2 clients (HQ) can also connect to the HQ and access the corresponding services.

However, the problem is that the IKEv2 clients (HQ) cannot access services running on the external site (EXT). It seems that the IKEv2 clients cannot access the S2S VPN.

Nothing blocked can be seen in the firewall.
I think there is still a route missing that is needed for the IKEv2 clients.

Can anyone help me with what I am doing wrong here or what is still missing?

Thank you very much!