Huawei P9 Guide De Démarrage Rapide page 6

Getting started
Follow the instructions in the following figures to set up your
phone. Before you insert or remove the SIM card, power off your
phone.
When using the SIM ejector pin, exercise caution to avoid
injuring yourself or damaging your phone. Keep the pin away
from children to prevent them from accidentally swallowing
it or injuring themselves.
Insert your SIM card in the correct card slot; otherwise, your
Caution
phone may not detect the card.
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