How to Activate Roaming?

Now my Sim card work well without Pin Code an after rebbot, I don't succeed to activate Roaming otion.
When I Go in menu Wifi>plus and click on Oerator, I see the white menu where I can activate Roaming but this menu always disaear before I can click on Option.
Is someone can confirm the same pb on this Ghost Menu :-)
Is there an other way to activate it?
Finaly I found an app with widget that can display the roaming menu.