ImranKhanKhi

I'm so sorry to inform you that based on the photo of your inverter's sticker, this is an obvious clone as it has multiple missing signs! The error you've got is most probably due to hardware damage not related to the firmware update at all, just as Coulomb described earlier.
The model name says IV (4) not III (3) just so that you know the difference, because they're two separate models. The best thing to do now is to take it to the repair center, or much better to return the unit or change the model entirely.
You can refer to the following thread by @Coulomb for signs of clone inverters:
https://forums.aeva.asn.au/viewtopic.php?p=71752#p71752

Dear are you from Pakistan? Because there are no v3 model in Pakistan thay are re branded v4 twin models. Are tou sure you are using correct firmware? 

I noticed this detail in his description, but I preferred proceeding with my previous reply hoping that it's just a miscommunication or mistiming of observed events, still F09 is worrying to me!
Indeed, it does so, my VM IV Twin always disconnects all other power inputs and outputs, PV, AC IN, and AC OUT. Although, I have no idea about other models.

Since you didn't even click on the Update Firmware button, I don't think that the firmware had anything to do with it. I'm guessing that your inverter suffered from "infant mortality". It's rare, but it happens. Just get it replaced or repaired under warranty. 
I would only ever use battery power for the reflash, as Tarek says. It may not matter, indeed I can't think how it would matter, unless the DSP can disable the AC power supply somehow. 
You may be able to reflash even with fault code 09 showing, but it will likely still be there after the update. 

@ImranKhanKhi, there's one major step you did completely wrong! You need to keep battery power connected to your inverter, not AC, and disconnect all else, as the reflash process runs on battery exclusively. Please repeat the same reflash process you described and I think everything will go as expected, you described all correct steps.
VM III Twin and VM IV Twin take the same firmware files, so far. Anyway, @ImranKhanKhi need to make sure that he has an original Voltronic inverter, a successful reflash now would indicate so.