If you mailed it in, it will probably take a bit longer. I emailed my letter to them and it took 15 business days for the academic review to drop off from the day they received it. Typically, once they receive your letter, it'll take 10-14 business days for them to review it. Once it drops off, they will mail your diploma and transcript as long as you are paid in full. I finished all of my exams before the review dropped off. Hopefully, I'll receive my diploma within the next couple weeks. Hope that helps.
Also, you can call Student CARE to check the progress on it, especially if you sent it snail mail vs. email.