Achievements still not popping

just like the tittle says"Achievements still not popping ".
just finished CE on legendary and didn’t get about 6 achievements through the game including skulls and actually completing the campaign.
also the lag is just atrocious…this game is so NOT fun on so many levels… it feels so incomplete and unpolished especially compared to the original…
very disappointed… and to boot they want us to pay for the nightfall. like i havnt bought every halo ever made and a bunch of halo related physical items…
please. i think my fan boy days are over…