diff --git a/charts/operator-wandb/charts/app/templates/_deployment.tpl b/charts/operator-wandb/charts/app/templates/_deployment.tpl
index 77f86f7b..81f7784f 100644
--- a/charts/operator-wandb/charts/app/templates/_deployment.tpl
+++ b/charts/operator-wandb/charts/app/templates/_deployment.tpl
@@ -258,7 +258,7 @@ spec:
             - name: GORILLA_INTERNAL_JWT_ISSUERS
               value: '["https://kubernetes.default.svc.cluster.local"]'
             - name: GORILLA_INTERNAL_JWT_SUBJECTS
-              value: '["system:serviceaccount:default:{{ .Values.global.weave-trace.serviceAccountName }}"]'
+              value: '["system:serviceaccount:default:{{ index .Values.global \"weave-trace\" \"serviceAccountName\" }}"]'
             {{- end }}
             {{- include "app.extraEnv" (dict "global" $.Values.global "local" .Values) | nindent 12 }}
             {{- include "wandb.extraEnvFrom" (dict "root" $ "local" .) | nindent 12 }}
diff --git a/charts/operator-wandb/charts/weave-trace/templates/serviceaccount.yaml b/charts/operator-wandb/charts/weave-trace/templates/serviceaccount.yaml
index fbe27b28..7f13fe6c 100644
--- a/charts/operator-wandb/charts/weave-trace/templates/serviceaccount.yaml
+++ b/charts/operator-wandb/charts/weave-trace/templates/serviceaccount.yaml
@@ -1,4 +1,7 @@
 {{- if .Values.serviceAccount.create -}}
+{{- if (empty .Values.global.weave-trace.serviceAccountName) -}}
+{{- fail "Values.global.weave-trace.serviceAccountName cannot be empty if serviceAccount.create is true" -}}
+{{- end -}}
 apiVersion: v1
 kind: ServiceAccount
 metadata: