Go to Maintenance > TR-069 Client. Set WAN Interface used by TR-069 Client to Multi_WAN, and then
3
select Cellular WAN 2.
7.6 Cellular SIM Configuration
Use this screen to enter a PIN for your SIM card, in order to prevent others from using it.
Entering the wrong PIN code 3 consecutive times locks the SIM card,
after which you need a PUK (Personal Unlocking Key) from the service
provider to unlock it.
Chapter 7 Broadband
Nebula Mobile Router User's Guide
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