diff --git a/src/App.jsx b/src/App.jsx
index adbafb7..05136ff 100644
--- a/src/App.jsx
+++ b/src/App.jsx
@@ -17,7 +17,10 @@ const App = () => {
   varsRef.current = { previousLocation };
 
   useEffect(() => {
-    if (location.pathname !== varsRef.current.previousLocation.pathname) {
+    if (
+      location.pathname !== varsRef.current.previousLocation.pathname ||
+      location.search !== varsRef.current.previousLocation.search
+    ) {
       window.scrollTo(0, 0);
     }
   }, [location]);
diff --git a/src/utils/challenge.js b/src/utils/challenge.js
index 4ac03eb..dbd13e7 100644
--- a/src/utils/challenge.js
+++ b/src/utils/challenge.js
@@ -63,6 +63,12 @@ Joi.type = () =>
       ) || null
   );
 
+Joi.validDate = () =>
+  Joi.alternatives().try(
+    Joi.date(),
+    Joi.any().custom(() => null)
+  );
+
 export function getCurrencySymbol(prizeSets) {
   return constants.CURRENCY_SYMBOL[_.get(prizeSets, "[0].prizes[0].type", "")];
 }
@@ -141,8 +147,8 @@ const queryScheme = {
   tracks: Joi.array().items(Joi.track()),
   search: Joi.string(),
   tags: Joi.array().items(Joi.string()),
-  startDateEnd: Joi.date(),
-  endDateStart: Joi.date(),
+  startDateEnd: Joi.validDate(),
+  endDateStart: Joi.validDate(),
   sortBy: Joi.string().valid("updated", "overview.totalPrizes", "name"),
   groups: Joi.array().items(Joi.optionalId()).unique(),
   events: Joi.array().items(Joi.string()),