Catastrophic failure after firmware and Luban update - New 10w laser not working either on Snapmaker 2.0 350T

Your Luban version is known for connection issues, i would suggest to downgrade to a older version like 4.4.0 (there is also a newer version available but it was released freshly so who knows if it could connect to the machine).

Here is a thread about firmware upgrade for using 10W Laser, hope it helps: