404 Error when trying to create a sitemap

@ meerderideen I think you didn’t understand the topic’s problem. Virtual or not it’s not the problem. Every php page in WP is virtual, but you can find it at their addresses. I’m talking about sitemap’s 404 error, no other.

when such problem occurs to me . i just publish a couple of test posts with few hours in between and then it automatically start to build it again

For me this worked: disable the sitemap feature by unchecking the box, save, and then check on again. Now maps are visible.
Conclusions that I have drawn after repeated experiences of this kind: after any update or upgrade or big modification check the Yoast sitemap, because it’s not stable or reliable.
In these cases, might works:
1) Click save in the sitemap’s page settings
2) Click save in the permalinks plugin page settings
3) Disable the sitemap feature, save, and then check back

That worked fine, thanks, think I’ll bookmark this for future upgrades as it seems it regularly goes daft.

I tried your way but my error didnt go away. I deactivated the xml sitemap featured and installed google xml and google images xml

Thank you @tizz! Your solution worked for me.