BQ35100: SOH is always 0%

Tool/software:

Hello, 

I have programmed the fuel gauge in SOH mode. It was working perfectly, giving voltage, temperature, design capacity and SOH upon request by their corresponding commands. However, for some reason I don't know it started to give a very low value of SOH while the voltage was 2.7 V (I am using a CR2450) every time I ran it until now that for every battery I obtain 0 %. I tried to fix it by resetting the fuel gauge with 0x0041 and put it in SEALED mode after the configuration (so the CONTROL_STATUS register goes from 0x4081 to 0x6081). Debugging is not giving any result because the other 3 parameters are giving a correct value. I have tried putting Operation Config A in both 0x85 and 0xA5 and I get the same. I haven't performed calibration because it was working without it.

So what's going on with my fuel gauge to stop working correctly?

The function where I read all parameters is this in C:

void gau_readings_get(uint16_t u16_voltage, uint8_t u8_SOH, uint16_t u16_temperature, uint16_t u16_capacity)
{
  u16_voltage = gau_volt_read();
  u16_temperature = gau_temp_read();
  u16_capacity = gau_cap_read();
  u8_SOH = gau_SOH_read();
  SYSTICK_DelayMs(1000);
}

And the function gau_SOH_read() is this one:

static uint8_t gau_SOH_read(void)
{
/*Reading variables*/
  uint8_t u8_SOH[1];

  GAUGE_EN_Clear();
  SYSTICK_DelayMs(10);
  GAUGE_EN_Set();
  SYSTICK_DelayMs(1000);

  SERCOM4_I2C_WriteRead((uint16_t) u8SlaveAddr,
u8SOHAddr, (uint32_t) 1,
&u8_SOH[0], (uint32_t) 1);

  while(SERCOM4_I2C_IsBusy());


  return u8_SOH[0];
}

Thanks in advance.

Carlos