help with the BQ40Z50 and "DA register"

good day, Colleagues,

My customer tries to implement the BQ40Z50 for 1S configuration, but the register "DA configuration" doesn't answer. Also the FET enable command (command 22) doesn't work.

Could you be so kind and tell me, what customer should check? maybe you have steps how to start to work with the IC and maybe customer should apply some bias or logic levels to the pin(s)?

Customer also says, that IC answers on version number or number. I think, this means, that the bus works. I can send also a schematic for review, if you give me an address.

Thank you, Mike