diff --git a/overcloud.j2.yaml b/overcloud.j2.yaml
index 639dd59c96..1710e43a79 100644
--- a/overcloud.j2.yaml
+++ b/overcloud.j2.yaml
@@ -762,7 +762,7 @@ resources:
 {% endfor %}
       service_bootstrap_node_ip:
         yaql:
-          expression: dict($.data.l.where($ != null).selectMany($.items()).groupBy($[0], $[1]).select([$[0], $[1].flatten().first()]))
+          expression: dict($.data.l.where($ != null).selectMany($.items()).groupBy($[0], $[1]).select([$[0], $[1].flatten().first(null)]))
           data:
             l:
 {% for role in roles %}