diff --git a/lib/obp60task/NetworkClient.cpp b/lib/obp60task/NetworkClient.cpp
index b8ebaee..371f3b4 100644
--- a/lib/obp60task/NetworkClient.cpp
+++ b/lib/obp60task/NetworkClient.cpp
@@ -10,10 +10,20 @@ extern "C" {
 // Constructor
 NetworkClient::NetworkClient(size_t reserveSize)
     : _doc(reserveSize),
-      _valid(false)
+      _valid(false),
+      _jsonRaw(nullptr),
+      _jsonRawLen(0)
 {
 }
 
+NetworkClient::~NetworkClient() {
+    if (_jsonRaw != nullptr) {
+        free(_jsonRaw);
+        _jsonRaw = nullptr;
+        _jsonRawLen = 0;
+    }
+}
+
 // Skip GZIP Header an goto DEFLATE content
 int NetworkClient::skipGzipHeader(const uint8_t* data, size_t len) {
     if (len < 10) return -1;
@@ -324,6 +334,13 @@ bool NetworkClient::httpGetGzip(const String& url, uint8_t*& outData, size_t& ou
 bool NetworkClient::fetchAndDecompressJson(const String& url) {
 
     _valid = false;
+    _doc.clear();
+
+    if (_jsonRaw != nullptr) {
+        free(_jsonRaw);
+        _jsonRaw = nullptr;
+        _jsonRawLen = 0;
+    }
 
     uint8_t* raw = nullptr;
     size_t rawLen = 0;
@@ -333,14 +350,18 @@ bool NetworkClient::fetchAndDecompressJson(const String& url) {
         return false;
     }
 
-    DeserializationError err = deserializeJson(_doc, raw, rawLen);
-    free(raw);
+    // Parse in zero-copy mode and keep the backing buffer alive in the class.
+    DeserializationError err = deserializeJson(_doc, reinterpret_cast<char*>(raw), rawLen);
 
     if (err) {
         Serial.printf("JSON ERROR: %s\n", err.c_str());
+        free(raw);
         return false;
     }
 
+    _jsonRaw = raw;
+    _jsonRawLen = rawLen;
+
     if (DEBUGING) {Serial.println("JSON OK!");}
     _valid = true;
     return true;
diff --git a/lib/obp60task/NetworkClient.h b/lib/obp60task/NetworkClient.h
index 5d3f448..80e0703 100644
--- a/lib/obp60task/NetworkClient.h
+++ b/lib/obp60task/NetworkClient.h
@@ -12,6 +12,7 @@
 class NetworkClient {
 public:
     NetworkClient(size_t reserveSize = 0);
+    ~NetworkClient();
 
     bool fetchAndDecompressJson(const String& url);
     JsonDocument& json();
@@ -20,6 +21,8 @@ public:
 private:
     DynamicJsonDocument _doc;
     bool _valid;
+    uint8_t* _jsonRaw;
+    size_t _jsonRawLen;
 
     int skipGzipHeader(const uint8_t* data, size_t len);
     bool httpGetGzip(const String& url, uint8_t*& outData, size_t& outLen);