I have a Kogan Agora dual sim smartphone that has worked perfectly for almost two years. I use sim 1 for calls and sms and sim 2 for data. A few weeks ago the phone started defaulting to use sim 1 for data so I have been billed for excess data use. It doesn't matter how many times I go into settings and specify use for each sim, the phone will use sim2 once for data and then change back to sim 1. hope someone can help. Thanks.