diff --git a/modules/justpremiumBidAdapter.js b/modules/justpremiumBidAdapter.js
index 7bd32531ccd..1f84feee7d1 100644
--- a/modules/justpremiumBidAdapter.js
+++ b/modules/justpremiumBidAdapter.js
@@ -100,7 +100,7 @@ export const spec = {
 
   getUserSyncs: function getUserSyncs(syncOptions, responses, gdprConsent, uspConsent) {
     let url = 'https://pre.ads.justpremium.com/v/1.0/t/sync' + '?_c=' + 'a' + Math.random().toString(36).substring(7) + Date.now();
-    if (gdprConsent && (typeof gdprConsent.gdprApplies === 'boolean')) {
+    if (gdprConsent && (typeof gdprConsent.gdprApplies === 'boolean') && gdprConsent.gdprApplies && gdprConsent.consentString) {
       url = url + '&consentString=' + encodeURIComponent(gdprConsent.consentString)
     }
     if (uspConsent) {