Yii2: cannot get primary key after $model->save()

[chaintng]

After call $model->save();
and i tried to get the last INSERT record id via $model->[PRIMARY KEY NAME]

but the return is just empty string ''

I think it might be a bug.

[chaintng]

i also did tried $model->primaryKey but it still got the empty string.

The weird thing is that other model is work just fine...

I check the database structure already and that table has set primary key with auto incremental...

[chaintng]

Okay, it's because there has primary key field in the rules... after remove that, it works now

[gledsoneduardo]

$model->getPrimaryKey();

see get first