diff --git a/src/services/broker/broker_read_model_service.py b/src/services/broker/broker_read_model_service.py
index 88eca14..9660f7b 100644
--- a/src/services/broker/broker_read_model_service.py
+++ b/src/services/broker/broker_read_model_service.py
@@ -193,7 +193,7 @@ class BrokerReadModelService:
             raise ValueError("okx_read_credentials_missing")
         request_path = path
         if params:
-            query = httpx.QueryParams(params).render()
+            query = str(httpx.QueryParams(params))
             request_path = f"{path}?{query}"
         timestamp = datetime.now(timezone.utc).isoformat(timespec="milliseconds").replace("+00:00", "Z")
         sign_input = f"{timestamp}GET{request_path}".encode("utf-8")