Huawei STK-L21 Guide De Démarrage Rapide page 7

Dual SIM Card Management
Your device supports dual card dual standby. Under
Settings > Wireless & networks > Dual SIM settings,
select the default mobile data card and calling card as
needed.
•
4G service depends on the support of your network
provider and its deployment of relevant services.
Please contact your network provider to activate 4G
service.
•
4G service may be unavailable in certain areas due
to network interference.
•
If this guide is inconsistent with the description on
the official website, the latter prevails.
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