You should power off/on the device when switching SIM cards. A hot swap is not supported by Lumia 1520.
- I cannot download or get application updates when first starting the Store app on my Lumia. How can I resolve this issue?
- How do I find the MAC address and other phone information of my Lumia phone?
- Will I get “Hey Cortana” voice activation after Lumia Denim update?
- Are there limitations for Hey Cortana on my Lumia?
- What is 'Hey Cortana' for my Lumia phone?