Booting Issue for the new arrived Flux Delta +


I just got my Flux Delta +, and I assemble it according to the manual. After I plug in the power cable, the LED keep blue breathing. I have been waiting for a long time, but the LED is still blue breathing. In the manual, that seems mean it is booting. And should turn to white, if it is normal?
I also tried to connect my PC with USB cable. But studio can not detect anything.
Could you help to provide some suggestions?
Thanks in advance…