How to modify LTC3886 NVM

Now we need new VOUT, want to modify EEPROM. firstly we use PMBUS to download  parameter in RAM, and it work OK.

 Page1 (old parameter , has been stored in NVM,   and VOUT 3V )
0x26 -> 0x2d9a #Page 1 VOUT_MARGIN_LOW 2.85V
0x43 -> 0x2ca4 #Page 1 VOUT_UV_WARN_LIMIT 2.8V
 0x44 -> 0x2b33 #Page 1 VOUT_UV_FAULT_LIMIT 2.7V
0x21 -> 0x3000  #Page 1 VOUT_COMMAND 3V
0x25 -> 0x3266 #Page 1 VOUT_MARGIN_HIGH 3.15V
0x42 -> 0x335c #Page 1 VOUT_OV_WARN_LIMIT 3.2V
0x40 -> 0x34cd #Page 1 VOUT_OV_FAULT_LIMIT 3.3Vv

  PAGE 1 (the new we need, VOUT is 2.7V )
0x26 -> 0x290A  #Page 1 VOUT_MARGIN_LOW 2.565V  -5%
0x43 -> 0x2864  #Page 1 VOUT_UV_WARN_LIMIT  2.5245V  -6.5%
 0x44 -> 0x282D  #Page 1 VOUT_UV_FAULT_LIMIT  2.511V  -7%
0x21 -> 0x2B33  #Page 1 VOUT_COMMAND  2.7V
0x25 -> 0x2D5C  #Page 1 VOUT_MARGIN_HIGH  2.835V  5%
0x42 -> 0x2E70  #Page 1 VOUT_OV_WARN_LIMIT 2.9V   7.5%
0x40 -> 0x2F85  #Page 1 VOUT_OV_FAULT_LIMIT  2.97V  10%
( We test VOUT, and  it  is 2.7V,NO alarm/fault,   we think it can work OK in RAM )
 
->Then we write command 0x15, hope to store parameters  in  EEPROM.

When we repower up, the VOUT become 3V again. And find the parameter in EEPROM  is the old version again.

Could you help check how we can modify LTC3886 EEPROM.   And we can't find software example