Hi,
Thats was very sadly accident.
Wrong wiring vcc and vccq can lead to box damage, and in worst case it may can kill mcu inside box.
In your case, because box can still operate, it may ic regulator problem, and it need to be replace.
Please ask your reseller, it may can be repair if your reseller have part.
This can be warning to everyone, be carefull, and please double check your connection in ISP operation.