While holding the buttons, connect the phone to your PC via the USB cable.

If your phone is hard-bricked (black screen), it is likely already in EDL mode silently. If it is boot-looping:

Ensure all partitions are checked (if you are doing a full fix). Click the green button in the SP Flash Tool. Important: Turn off your ZTE Blade V30 Vita.

The phone does not turn on at all, or only shows a black screen.

If you want, I can:

This paper assumes a scenario where a critical vulnerability or operational failure was discovered in the stock firmware and subsequently resolved through a patch or custom development.