RAK 7204 unable to flash

Issue:unable to flash after reloading bootloader

Setup:

Server:

Details:I attempted to downgrade the firmware from 3.0.0.14Beta to 3.0.0.12HT from the website however the device wouldn’t come out of boot mode once the firmware was loaded it stated that no legal image was loaded, I downloaded the available boot loader V 3.0.2 and re-wrote the boot loader okay however I am now unable to flash the device any firmware, I open port, select firmware and click start however it never progresses, it just times out. I have tried with firmware 3.0.0.12 - 3.0.0.9. the device does show RUI Bootloader Version:3.0.2 when using the serial port tool and at+version is sent. are you able to assist.