I'm not completely certain, whether you need to insert the SIM card on the left or right side. The information I have does not fully address this specific situation.
According to the manual, you remove the battery cover on the back of the router and insert the SIM card into the SIM slot while paying attention to the outline marking the slot. The contacts of the card must face the router. It does not explicitly state «left» or «right» but refers to the position on the back.
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