On my phone I use ProtonVPN, which is always enabled. But with VPN enabled, the assistent fails, as shown in the screenshot 
It does not matter whether I use it in the browser or the kagi app; the result is the same. It alsook does not matter whether I have netshield enabled (protonvpn's tracking protection).
I now have to use split tunneling to exclude the kagi app from the VPN connection, but that defeats the purpose of using a VPN.
Don't know whether it is a ProtonVPN or a Kagi issues; will report this issue there as well.
Everything should just work, either with or without VPN.