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Insert the SIM card into the top slot by a chip on the SIM card facing down. Bottom slots – with the chip facing up.
By default the LR card is connected with SIM slot #1, the slot cannot be used for a different purpose.
Please check if you are using the correct SIM slot. For the modem inserted in the bottom mini-pcie slot, you need to use either sim slot 2 or sim slot 3. And the used sim slot needs to be selected in RouterOS.
CLI command to select the sim slot: /system routerboard modem set sim-slot=2
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