southernpride,
You said that you turned the test in and passed. Did you test for a company single-hand in their facilities or are you an independent contractor that performed the weld test and then sent it in to a lab? If the latter then they should have asked or you should have specified which code you were testing to. The AWS D1.1 code has many different test; some on plate some on pipe and tube steel. So AWS D1.1 has pipe test but the acceptance criteria is different than ASME IX test.
This is how it works...usually. The mech. contractor has a job. It may be chill water, steam, oil, condensate or gas pipe. The contract documents (drawings and specifications)that they are working to will determine the code that applies to the pipe system(s) that they are installing. It may be ASME 31.1, 31.3, 31.8, 31.9, API codes but I have never seen D1.1 pipe test called for in the specs. for mechanical piping except for the support and hanger welds. In the specs it will require that the welder be qualified to ASME IX for the codes just mentioned except for the API code.

You can tell the contractor what test and certs that you have and then ask what certification you need to perform the work for them. Some MC's know very little about welding, codes, test etc. Some know ALOT. If you do not have the right qual. perhaps you can test with them or elsewhere so you don't miss out on the opportunity to do their work.
You might call the testing agency and see if it was a mistake on there end. It's possible that they put it on the wrong form or just plugged in the wrong code. If they Rt'd it they should still have the film and can compare it to Sect. IX acceptance criteria and provide the correct documentation if it was just a simple mistake.
Some of the more experienced folks on here may see a problem with that or provide a better solution. Good luck with resolving the problem and getting the work.