If there's only one SIM card in the phone, it's
ready to use.
With two SIM cards inserted, you can choose
to use one or both of them:
Go to
Settings
>
SIM cards
and tap the
on/off button to enable or disable SIM1 or
SIM2.
Dual SIM phone settings
2
3
4
English
1
SIM 1
SIM 1
2
SIM 2
SIM 2
SIM cards