Missing all Xbox achievments

Hi Miss Vanquish. All the achievements on Xbox One, will not appear on Xbox 360. You quiet, achievements will be there.

Thanks i did call and they had me remove all profiles and hard reset, ive unlocked other achievements but hasn't fixed it, said he didnt have any other suggestions but to post here. So just wait an see i guess

I'm still having this same issue!! (5/20/20)

All of my 360 achievements are still normal but all my xbox one games got wiped out! I'm still down almost 10k gamerscore. What I've noticed though is the xbox games I've played so far have returned to normal but all the other ones are still saying 0, until
you click on the game itself to view the stats, then it shows what gamerscore I still have on that game. I tried unlocking new achievements but that didnt help. For the month of May so far it says I've earned 5,270 gamerscore... which is most definitely not
the case. Hopefully this issue gets resolved asap.

Purtroppo questo è un Bug temporaneo che sta affliggendo molti profili, non ti scoraggiare è solo una cosa momentanea. Presto torner tutto normale, le cose si stanno facendo solo un pochino lunghe è normale per via del casino intorno a noi, se ci pensi
siamo tutti a casa e i server sono allo stremo.

This has happened before for many gamers. Usually unlocking an achievement can help bring it all back. If that doesn't work, then try removing the profile from the console, then redownload it.