I think the "approval for nationality" your talking about is that your company apply only for visa. If the visa they applied was approved, it needs to be transfer to your name. Ask your company if they already transfer it your name. If they say they already transfer the visa to you, thats the time you can check it in the MOI website using your passport number. From there, you can determine if it is under review or its already approve.

If you are sure that the "approval for nationality" was already approved, get the application number from them and try to check it in the MOI website.