Omnibus F4 not working


I think I burnt something on my FC Omnibus F4, when I connect the battery it is just blue led and cannot connect in betaflight (does not recognized when I connect it through micro USB)?Do you have any idea?

assume you think you burnt it because you saw some smoke, sniff it if its smells burnt its toast.
should be a constant green light and a blue light that flashes for a few seconds.