I have 3 hashboards of BHB42651 but dosent work with any firmawre.
The BHB42651 is just another variant of the S19j pro, there are like a dozen different variants for this model, not sure why Bitmain does that, I assume you bought the 100th version labeled as S19 pro 100th? what firmware have you used? did you try Braiins? also what type of control board did it come with?