Switch to permalinks – how to alter old (page_id=xx) links in pages

Hello,

I have WP 4.1, with Elegantthemes’s divi theme.

Today I changed Permalinks, from default to “Month and Name”.

Everything seems to work ok, the menu is ok and both of the links work (the permalink style and the ?page:id=xx style).
Although is seems it works more like cathegory-name because there is no month is the link. But this does not bother me.

My problem is, that while the menu changed it’s links to permalinks (i go over the menu and see http://www.xxx.com/xxx/yyy/zzz), the links in pages did not. So I open a page, and the links in that page are http://www.xxx.com/?page_id=xx. How do I alter these links to permalinks? It works of course, but i believe even the links should be in permalink style. I can do it one by one, but I really don’t want to do that.

Is there any plugin for this, etc? Something like Velvet Blues, but fixing the links to permalinks? Or may this be a divi problem?

I tried to google it, but I’m probably not able to set the query specific enough – all I see is broken permalinks.

thank you