It sounds like your Reporter Lysis Buffer might not be working on your HeLa cells because the lysis conditions aren’t optimal for this cell type. Even though you’ve tried fresh buffer and longer lysis times on ice, HeLa cells can sometimes be resistant to lysis with standard RLB due to their strong adherence and membrane properties. You might want to try adding a mild detergent like 0.1% Triton X-100 to your lysis buffer or increasing the incubation time at room temperature instead of on ice. Also, gently scraping the cells after incubation might help to detach and lyse them more effectively. Others have reported similar issues and found that modifying the buffer composition or lysis protocol can improve results.