No check on the revenue stamp on my post card

Hello,

I have applied for extension of period of stay (long term resident). I have received the reply postcard, and it seems ambiguous, I’d need your opinion on it.

It is postcard, not letter.
It came as registered mail, and the 4000 yen stamp is not marked.

It, however, has no specified date and hour to appear, just a deadline as always, normally.

Also, it is not written that only the applicant personally can go.

And the counter is the normal A1 counter, not consultation counter.

With these details above, what is the case?
Please tell your opinion/experience.

Thank you very much in advance to all you guys.