Jumper t lite I seem to have bricked it

Hi everyone.
I’m an oldish (64yrs) newcomer to all things drone.
I bought a few of the ‘toy’ drones and those that didn’t immediately try to climb trees or simply float away on the slightest breeze gave me a lot of fun so I bought a Bugs7 with gps, with which I had even more fun so I finally decided to lump for a combo of an Emax BabyHawk and a Jumper T Lite transmitter.
And blimey! A hobby that was switch-on-and-play has now become a blimmin’ nightmare!

Now, while trying to learn to update the firmware, I have somehow managed to mess the transmitter up so badly it doesn’t even light up the screen any more. It acts, for all the world, like it’s dead.
It’s not though. If I plug it in without holding down any buttons, I get that dum-diddle-um sound when Windows recognises something plugged into one of the USB ports. Looking on the Control Panel, it says it recognises it as an STM32 Bootloader although the transmitter itself acts like the battery is flat.

Is there anything I can do to save it, do you think? I really would appreciate some help here. I’m going barmy with it.
]Thanks in advance. :slight_smile: Nigel.