diff --git a/src/spaceone/core/pygrpc/client.py b/src/spaceone/core/pygrpc/client.py
index 7fe083b..08bb8d9 100644
--- a/src/spaceone/core/pygrpc/client.py
+++ b/src/spaceone/core/pygrpc/client.py
@@ -111,9 +111,11 @@ def _retry_call(
 
         while True:
             try:
+                _LOGGER.debug(f"client._retry_call.start!!!")
                 response_or_iterator = continuation(
                     client_call_details, request_or_iterator
                 )
+                _LOGGER.debug(f"client._retry_call.response_or_iterator Success!!!")
 
                 if is_stream:
                     response_or_iterator = self._generate_response(response_or_iterator)
@@ -123,7 +125,11 @@ def _retry_call(
                 return response_or_iterator
 
             except Exception as e:
+                _LOGGER.debug(f"client._retry_call.Exception: {e}")
                 if e.error_code == "ERROR_GRPC_CONNECTION":
+                    _LOGGER.debug(
+                        f"client._retry_call.retry_call: {retries}  ||  _MAX_RETRIES: {_MAX_RETRIES}"
+                    )
                     if retries >= _MAX_RETRIES:
                         channel = e.meta.get("channel")
                         if channel in _GRPC_CHANNEL: