Expiration of Zairyu card

What to do if zairyu card expires outside Japan? What are the procedure to do ?Is immigration lawyer needed ? Who to ask things aside from immigration officers? Does it mean an expired zairyu card is losing permanent residency in japan as well?

https://www.japan-guide.com/forum/quereadisplay.html?0+165233

There is something in there ..

If your card expired outside Japan you cannot enter even if you have a re-entry permit.
Your visa status is what count.
So in this case you are losing your status and therefore you re-entry permission.
Since you do not have the right requirements at this moment you better to call immigration and explain what happened and hear their reaction.

You can go as tourist to Japan and try to fix the issue.
But wont be easy since you have let it expired.

Just my day is totally wrong and I have asked this myself to the immigration. You just need valid re-entry to enter Japan. They don�ft even ask for your zairyu card at immigration

Some airlines may create problem but it�fs because they are ignorant

Note, expiration of the residence card and expiration of the period of stay are not necessarily the same thing, especially for permanent residents.

In particular, for PRs expiration of the residence card does not cause loss of status.

Does OP mention PR status???