Ensure your OnePlus 6T is completely powered down and disconnected from any charging source before proceeding.
Power down the phone completely.
Insert a SIM card removal tool into the small hole located in the upper-left side of the phone.
Be cautious not to damage the phone's components when loosening binding glue.
Insert a Jimmy under one of the heated corners to lift the phone slightly.
Use high concentration (>90%) isopropyl alcohol and a lint-free cloth to thoroughly clean any remaining adhesive residue from both the back cover and frame.
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