network: fix send_multiple_requests

electrum/network.py

@@ -1161,6 +1161,8 @@ class Network(PrintError):
                 res = e
             responses[iface.server] = res
         async with TaskGroup() as group:
-            for interface in self.interfaces.values():
+            for server in servers:
+                interface = self.interfaces.get(server)
+                if interface:
                     await group.spawn(get_response(interface))
         return responses