Cannot edit form: cascading choices can only reference one choice list

Hello, I can preview and fill my Kobo form but cannot edit it on KoboTool Box. I get the message Error loading survey cascading choices can only reference one choice list:.
I have checked previous discussions on this topic with the community and tried out everything including setting up my cascading choices on XLS and validating through the online validator (which does not throw up any major changes). Please help me fix this?
Thanks!

Welcome to the community, @nidhi_h! Would you mind validating your XLSForm through this online validator? It should help you identify syntax issues if any within your XLSForm.