First of all, thank you very much for issuing this PQR.
We investigated this case and confirmed that the failure ratio is not high.
Therefore, we consider that this is a rare case(not a common issue), and we would like to close this PQR once.
If you received similar failure report from the field frequently, please issue new PQR/QRS for all of the failed units.
We will investigate the root cause of this case deeply as soon as we confirm failure frequency keeps increasing.
We will also continue monitoring the warranty submission situation of this case, even after the PQR is closed.