IAQ Accuracy Resets (0) when my MCU Goes into sleep mode and then wake up

Hello I am working on BME680 sensor for my enviromental project, As per suggestion I am using BSEC Library, I have intedgrated with my MCU and it works fine , while reading continuously , This was my fist phase of the project which is completed, But now I want to my MCU to be in low power mode , My MCU will goes into sleep mode for 5 mins and wake up collect data from the BME680 and then goes to sleep. But the provlem occurs here , when the MCU runs in continous mode IAQ accuracy works fine ( 0 , 1 ,2 and 3) , Like for example when the IAQ accuracy is set to 1 or 2 , and then I active the sleep mode , after five minutes when the MCU wakes up , I notice that IAQ accuracy is reset to zero (0). I am working from last one week yet the problem still exists.
Any help regarding this will much be appreciated.
Thanks

This is the initialization

IoT endless loop

 while (1)
    {
        if ( onoffflag == 1 )
        {
          /* get the timestamp in nanoseconds before calling bsec_sensor_control() */
          time_stamp = get_timestamp_us() * 1000;
        
          /* Retrieve sensor settings to be used in this time instant by calling bsec_sensor_control */
          bsec_sensor_control(time_stamp, &sensor_settings);
        
          /* Trigger a measurement if necessary */
          bme680_bsec_trigger_measurement(&sensor_settings, sleep);
        
          /* Read data from last measurement */
          num_bsec_inputs = 0;
          bme680_bsec_read_data(time_stamp, bsec_inputs, &num_bsec_inputs, sensor_settings.process_data);
        
          /* Time to invoke BSEC to perform the actual processing */
          bme680_bsec_process_data(bsec_inputs, num_bsec_inputs, output_ready);
        
          /* Increment sample counter */
          n_samples++;
        
          /* Retrieve and store state if the passed save_intvl */
          if (n_samples >= save_intvl)
          {
            bsec_status = bsec_get_state(0, bsec_state_loop, sizeof(bsec_state_loop), work_buffer, sizeof(work_buffer), &bsec_state_len_loop);
            if (bsec_status == BSEC_OK)
            {
              state_save(bsec_state_loop, bsec_state_len_loop);
            }
            n_samples = 0;
          }

          /* Compute how long we can sleep until we need to call bsec_sensor_control() next */
          /* Time_stamp is converted from microseconds to nanoseconds first and then the difference to milliseconds */
          time_stamp_interval_ms = (sensor_settings.next_call - get_timestamp_us() * 1000) / 1000000;
          if (time_stamp_interval_ms > 0)
          {
            sleep((uint32_t)time_stamp_interval_ms);
          }
}