LG V60s after Android 11 have secure boot that locks NV items. If you try to write without unlocking the sec_config, the phone will reject the write and hard-brick. Therefore, this method is for advanced users only.
Use LG-Firmwares.com or similar repositories. Download the exact KDZ for your V60 model and region. Crucially: Do not flash a T-Mobile KDZ on an AT&T phone expecting the IMEI to return; it won’t. lg v60 imei repair work
This requires a rooted V60 with USB debugging enabled. LG V60s after Android 11 have secure boot
It is vital to note that altering an IMEI is strictly regulated. lg v60 imei repair work