No Show and refusing to pay

This is my first summer and already I have had a no show and someone refusing to pay saying they had no money even though I took a credit card payment but unbeknown to me it wasn’t honoured as the signal dropped out in the middle of it and the receipt did not say not authorised.
 Booking.com did not take commission but I am still hundreds of pounds out.  

I have someone booked today for a birthday I have decorated it for him as surprise for his girlfriend and baked a cake as requested saying he would pay when arrives now he is not answering messages for his arrival lunch time today what if this another no show what can I do I am so stressed with it all after all the hard work.

If Booking.com deal with payments how long does it take each guest visit to reach my account?