Dear Watanabe San,
About Key Button can not operate problem risky found in Market and Market claim.
If market claim found after designer added Spacer ,This is CTC problem.
Please investigate with production dept.
Why until date still with out Spacer sticking ?
Please sampling this lot by dis mental check some q'ty, If with out Spacer found.
Please request dis mental check all and stick Spacer follow ECN as CES Engineering issued.
Thank you & Best regards,
Puchong