Zend certified PHP/Magento developer

Magento2.4 mutitlple product url rewrite in magento2.4

In Magnet2.4.2, multiple sites use the same category product, product url is not rewritten

Such as:
I have two websites, a.com and B.com,
I created a new website, a.com, in the background of Magento2.4, added classified CAT and maxcat.
Access to products: https://a.com/maxcat.html
Then I added a new website in the background, b.com. I used the same classified products above that I visited
https://b.com/maxcat.html does not exist. You can only access https://b.com/1.html, where 1 is the product ID.
Why is that?