diff --git a/backend/helpers/cardApi.js b/backend/helpers/cardApi.js
index 12f591b..062b45b 100644
--- a/backend/helpers/cardApi.js
+++ b/backend/helpers/cardApi.js
@@ -57,6 +57,7 @@ function acquireToken(timeout) {
             port:     fullUrl.port || (isHttps ? 443 : 80),
             path:     fullUrl.pathname + fullUrl.search,
             method:   'POST',
+            family:   4, // Force IPv4 — IPv6 is unreachable from this network
             headers:  {
                 'accept':        'application/json',
                 'authorization': 'Basic ' + authString,
@@ -150,6 +151,7 @@ async function cardRequest(method, urlPath, body, options) {
                 port:     fullUrl.port || (isHttps ? 443 : 80),
                 path:     fullUrl.pathname + fullUrl.search,
                 method,
+                family:   4, // Force IPv4 — IPv6 is unreachable from this network
                 headers,
                 timeout,
             };