This model is hardware-capable of Dual SIM, but the South Korean variant (S/L/K) often limits this via software. You must flash a modified Combination File Custom ROM (like a J530F port) to enable the second SIM slot. IMEI Repair/Patch:
The term "Auto Patch Free" generally refers to using specialized software tools that automate the process of sending AT commands or exploiting the device's modem/diagnostic partition to remove the SIM lock restriction.
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