Help: Device not getting IP address (or in general just not working)

[Alxandr]

We recently bought one of these devices on tindie (order 315091), and we cannot get it working. When we connect it to ethernet and power, it sometimes get's an IP address, and sometimes not. It does show up on our router (so I can see it's MAC address) - but it seems it stops working pretty fast cause most of the times it doesn't even complete DHCP. I've never been able to ping the device, and it does not listen on port 23. I've also not been able to flash the device - no matter which of the flashing instructions I try to follow, I get the following error:

Invoking bootloader by method 1 (default) // <- or method 3 if I use the --invoke-bootloader 3
Opening port COM3, baud 500000
Reading data from .\CC1352P2_CC2652P_launchpad_coordinator_20220219.hex
Your firmware looks like an Intel Hex file
Connecting to target...
ERROR: Timeout waiting for ACK/NACK after 'Synch (0x55 0x55)'

I'm kind of stuck at this point, and need some help to continue.