Helm (jinja2): parse error "did not find expected key" at a non-existant further line - visual-studio-code

Question

This is my first question ever on the internet. I've been helped much by reading other people's fixes but now it's time to humbly ask for help myself.
I get the following error by Helm (helm3 install ist-gw-t1 --dry-run )
Error: INSTALLATION FAILED: YAML parse error on istio-gateways/templates/app-name.yaml: error converting YAML to JSON: yaml: line 40: did not find expected key
However the file is 27 lines long! It used to be longer but I removed the other Kubernetes resources so that I narrow down the area for searching for the issue.
Template file
{{- range .Values.ingressConfiguration.app-name }}
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
name: "{{ .name }}-tcp-8080"
namespace: {{ .namespace }}
labels:
app: {{ .name }}
chart: {{ $.Chart.Name }}-{{ $.Chart.Version | replace "+" "_" }}
release: {{ $.Release.Name }}
heritage: {{ $.Release.Service }}
spec:
hosts: # Is was line 40 before shortening the file.
- {{ .fqdn }}
gateways:
- {{ .name }}
{{ (.routing).type }}:
- route:
- destination:
port:
number: {{ (.services).servicePort2 }}
host: {{ (.services).serviceUrl2 }}
match:
port: "8080"
uri:
exact: {{ .fqdn }}
{{- end }}
values.yaml
networkPolicies:
ingressConfiguration:
app-name:
- namespace: 'namespace'
name: 'app-name'
ingressController: 'internal-istio-ingress-gateway' # ?
fqdn: '48.characters.long'
tls:
credentialName: 'name-of-the-secret' # ?
mode: 'SIMPLE' # ?
serviceUrl1: 'foo' # ?
servicePort1: '8080'
routing:
# Available routing types: http or tls
# In case of tls routing type selected, the matchingSniHost(resp. rewriteURI/matchingURIs) has(resp. have) to be filled(resp. empty)
type: http
rewriteURI: ''
matchingURIs: ['foo']
matchingSniHost: []
- services:
serviceUrl2: "foo"
servicePort2: "8080"
- externalServices:
mysql: 'bar'
Where does the error come from?
Why does Helm still report line 40 as problematic -- even after the shortening of the file.
Can you please recommend some Visual Studio Code extention that could have helped me? I have the following slightly relevant but they do not have linting (or I do not know to use it): YAML by Red Hat; amd Kubernetes by Microsoft.