DP83826I: Can not write address 25h register.

Part Number: DP83826I

Tool/software:

Hi team,

My customer want to use DP83826I in Motor driver. And find that they can not write address 25h register.

They can successfully write resisgter 27h and 18h. 

Q1:  Does 25h register support write instruction?

Q2: If answer is right, are there any reason why customer can not write it successfully.