Cancellation after COE is issued

Hello

I got COE for Japanese language for October intake but I cancelled to go to Japan. The school didn't collect any cancellation fees until now. I am not sure whether my COE is already returned to immigration or not.

Now, I am trying to go to work in Japan . Therefore, I need to apply COE again for work visa.
Is it necessary to apply my precious COE and statement of cancellation letter from the Japanese language school or other required by Immigration Bureau .

Did the school send you the COE? Do you have any information about that COE, like reference number and such.

By right you need to return the unused COE to Immigration or check with your local Japanese embassy.
COE have expiration date(valid for three months after its date of issue), so if you don't use it (enter Japan) by then, it will be cancel/void/expired.

So, when or how long is this ? When you is you 'new' COE application? Problem is when you have 2 or more COE in process at the same times.

It's all about timing. If you are in doubt contact the school or immigration to confirm.

Why not contact the school first to see if they sent the COE back to immigration? That would make more sense to do instead of asking people on a forum waiting for an answer when you should be contacting them immediately to see if you can still use the same COE without having to apply for a new one.

contacting them immediately to see if you can still use the same COE without having to apply for a new one.

OP want to apply for new COE for work visa. Previous issued/approved COE is for student visa.

No, you cannot use the old COE for work visa application.