diff --git a/bfxapi/rest/middleware/middleware.py b/bfxapi/rest/middleware/middleware.py
index 1e77a71..01f6f60 100644
--- a/bfxapi/rest/middleware/middleware.py
+++ b/bfxapi/rest/middleware/middleware.py
@@ -19,7 +19,7 @@ class Middleware(object):
         assert isinstance(self.API_KEY, str) and isinstance(self.API_SECRET, str), \
             "API_KEY and API_SECRET must be both str to call __build_authentication_headers"
 
-        nonce = int(round(time.time() * 1_000_000))
+        nonce = str(round(time.time() * 1_000_000))
 
         if data == None:
             path = f"/api/v2/{endpoint}{nonce}"
diff --git a/bfxapi/websocket/client/bfx_websocket_client.py b/bfxapi/websocket/client/bfx_websocket_client.py
index a8104be..4b3052e 100644
--- a/bfxapi/websocket/client/bfx_websocket_client.py
+++ b/bfxapi/websocket/client/bfx_websocket_client.py
@@ -174,9 +174,9 @@ class BfxWebsocketClient(object):
     async def __authenticate(self, API_KEY, API_SECRET, filter=None):
         data = { "event": "auth", "filter": filter, "apiKey": API_KEY }
 
-        data["authNonce"] = int(round(time.time() * 1_000_000))
+        data["authNonce"] = str(round(time.time() * 1_000_000))
 
-        data["authPayload"] = "AUTH" + str(data["authNonce"])
+        data["authPayload"] = "AUTH" + data["authNonce"]
 
         data["authSig"] = hmac.new(
             API_SECRET.encode("utf8"),