diff --git a/test/vpp_lo_interface.py b/test/vpp_lo_interface.py
index 9493a70..963123f 100644
--- a/test/vpp_lo_interface.py
+++ b/test/vpp_lo_interface.py
@@ -20,7 +20,7 @@
         self.test.vapi.delete_loopback(self.sw_if_index)
 
     def query_vpp_config(self):
-        dump = self.vapi.sw_interface_dump()
+        dump = self.test.vapi.sw_interface_dump()
         return self.is_interface_config_in_dump(dump)
 
     def is_interface_config_in_dump(self, dump):