fix object storage nil pointer deref error
diff --git a/openstack/objectstorage/v1/accounts/requests.go b/openstack/objectstorage/v1/accounts/requests.go
index a645115..66c46a9 100644
--- a/openstack/objectstorage/v1/accounts/requests.go
+++ b/openstack/objectstorage/v1/accounts/requests.go
@@ -43,7 +43,9 @@
 		MoreHeaders: h,
 		OkCodes:     []int{204},
 	})
-	res.Header = resp.Header
+	if resp != nil {
+		res.Header = resp.Header
+	}
 	res.Err = err
 	return res
 }
@@ -97,7 +99,9 @@
 		MoreHeaders: h,
 		OkCodes:     []int{201, 202, 204},
 	})
-	res.Header = resp.Header
+	if resp != nil {
+		res.Header = resp.Header
+	}
 	res.Err = err
 	return res
 }