What goes in the Common Interface slot on the TV

Why is my TV suddenly claiming that the CI+ module is not inserted ci slot lg tv - SPDIF 1ea Headphone output - CI Slot 1ea POWER Power Supply AC 100~240V 50-60Hz Standby Power Consumption city life slot CI Module for pay TV, which normally uses a different slot This LG for example, where some of their models carry the X Studio feature

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