H1B and H4 appointments taken together but spouse(H4) would not be able to attend

[MSocPrism]

Hi

I had taken a joint appointment of H1B(me) and H4(spouse) in Chennai Consulate. Unfortunately it seems there is a chance my spouse might not be able to come for the interview. What should I do in this scenario? Should I try to cancel the appointment and take a new appointment for me and for wife later? Or can I just appear for the interview alone and book a new appointment later? The scheduled interview is in next week btw.