What is the red warning triangle in top left hand corner after trying to get numbers from old sim card?

slide you finger from the very top of the phone and slowly drag you finger down, a grey box will drop down there should be a description of the error, usually you can just dismiss the error by clicking it because it will sort itself out, i get this error often because i swap sims aloy, its usually the google account signing itself out because you inserted a different sim thn registered with the google account, and have to manually sign it back in slide you finger from the very top of the phone and slowly drag you finger down, a grey box will drop down there should be a description of the error, usually you can just dismiss the error by clicking it because it will sort itself out, i get this error often because i swap sims aloy, its usually the google account signing itself out because you inserted a different sim thn registered with the google account, and have to manually sign it back in

thanks for the solution but y does it get hang often.... n everytime have to reset to company settings for its smooth functioning thanks for the solution but y does it get hang often.... n everytime have to reset to company settings for its smooth functioning