i tried this service, this guy tried a lot. something wrong with the device itself. i ordered oneplus 9 pro. 7T going to the hall of dead shelf, where 7t will have company of pixel 4a 5g , iPhone xs and mi 10t pro.
Sounds like the correct EDL driver is not installed for the MSM download tool to detect the phone.
If you are running windows 10 then here is the EDL driver and you need to be in test mode to allow the driver to install correctly.
here are the files... extract to their own folders and run test mode on as admin by right clicking it and run as admin and then reboot.
you will see test mode in bottom right of screen now install drivers for phone.
Sometimes you need to go into device manager and if you see yellow mark next to phone manually update the driver with the extracted driver.zip also try included adb setup to install phone drivers if needed.
Sometimes you may need to manually install the driver also from the driver folder by right clicking on android_winusb file and choose install it will say operation completed successfully.
If you have not already done so here is the link to the unbrick files pick the latest one 10.0.15 make sure you pick correct region for your phone.
Disclaimer: By attempting any of the processes listed in this thread you accept full responsibility for your actions. I will not be held responsible if your device stops working, catches fire, or turns into a hipster and claims to have been...
run the MSM download tool so its ready to go.... make sure phone is completely powered off this is important.
Make sure usb is NOT plugged into phone yet....hold both volume buttons together and keep holding and plug in usb cable you should see connected pop up on MSM tool.... let go of the buttons and quickly press start and carefully place phone down where it will not be disturbed and wait till it finishes re flashing and reboots.
Once finished run test mode off as admin and reboot PC / laptop back to normal windows 10.
Your phone should be fixed and running oxygen os 10.0.15 and it will auto update to os 11 via system updates should you want it too.