Sent my non US passport to ITIN dep. to get a number so my husband will be able to pay his taxes. We got the ITIN number and the taxes refund but my passport didnt come

Its been 7 and half months since we filed it. 
We received the taxes after 7 months and the ITIN after 4 months of filing it
What should I do to get my passport back i keep on calling them and they say they are investigating it. My passport have the US visa on it.