The lab has made fool of you, in combo test they should have tested both
HIV-1 P24 antigen and antibodies against HIV-1 & 2 envelope Glycoprotein. The report should also mention reactive or non-reactive as it is a qualitative test not quantitative. Yes, chemiluminescence is a 4th generation test. Your tests are in-conclusive.
Next Steps
Repeat the test at some reputed lab mentioning them explicitly that i want both
HIV antigen and antibody qualitative testing.