op3/t's kernels doesn't support last_kmesg since 14. Use /sys/fs/pstore instead. Keep in mind, that the content of /sys/fs/pstore needs to be copied on the very next reboot, otherwise it's gone. I.e.: if you boot to recovery after a crash, you need to copy pstore in this recovery session; if you tebot to system again, pstore has the logs for the rec9very session, not from the crash.
Sadly a logcat from after a reboot doesn't have any info on what happened before the reboot.
@All: does anybpdy expirience the issue
@abhibnl has described? I'm using a flip cover, which may have saved me from the above.