I'm using a Nexus 6P and I'm on the $45 1gb plan. Right now I'm in the Czech Republic and just turned on data roaming to try and connect to a cellular network. When I click on 'Choose automatically' from the available networks settings menu, I receive a message saying unable to connect to network. Please try again later. Is there a reason I'm not able to even register on a cellular network here? The reason why I'm looking to do this is because I bought the international text $15 Thanks!