If you purchased your computer from Dell retail sales (if you bought a Studio, you did), I would recommend contacting your credit card company and reporting that the item has not shipped and you would like to dispute the charge. Once you have done that, go to the small/medium business/government area and purchase through there. Dell's retail sales group does not have the ability to ship to APO/FPO addresses - only the large business/government sections have that ability.
This is an ongoing issue and has been so for many years. I used to work at Dell supervising the last group of tech support representatives in the retail division at the corporate offices and encountered this issue on a regular basis.
One last possible chance - contact either the government support group by phone/email/chat and give them your order number and request they ship to an APO/FPO address. I doubt this will help, though. Again, your best bet is to cancel your order with Dell (or your bank) and reorder through the proper division there.
Since Dell has outsourced their entire retail support division, only their government/large business support is still domestic and they will be the only group likely able to help you.
Best of luck to you and thank you for your service! Although I am not supportive of our troops being put where they currently are, I am very proud that you are serving and hope you stay safe.