Sales Tax Exemption

We are a Federal government organization, U.S. Air Force, and as such are tax exempt. I have spoken to customer service and they told me to send our tax exempt status paperwork( removed for security), I have done this and have heard nothing back and the sales tax is still being applied to our bills. What do I need to do to get this resolved? This is the text of the e-mail that I originally sent back on 23 February 2016: Good day, I spoke to one of your customer service personnel yesterday (removed for security) about setting up Tax Exempt status for our two Comcast Business accounts as we are a Federal Government agency and as such are not allowed to pay sales tax when paying bills with our Government Purchase Card, which is the method with which we pay the fees for these accounts. She had instructed me to send the request and our documentation to this e-mail address, so that is what I am doing. The accounts involved are as follows: (removed for security) I have attached our IRS Employer Identification Number Notice, as well as supporting documentation from the California Board of Equalization to support this request. If there are any questions or your require further information from me please feel free to contact me at (removed for security)