Accelerometer Reading 0.5g for z-axis instead of 1g


I am using DWM1001 customized code to read accelerometer data. In the output, when the chip is stable it is reading 0, 0, 0.5g (x, y, z). The raw value is 8196 instead of 16384.

Following are the register values that I used to initialize the accelerometer.

uint8_t value_ctrl_reg1 = 0x57; // Turn on the sensor, enable X, Y, and Z ODR = 100 Hz
uint8_t value_ctrl_reg2 = 0x00; // High-pass filter disabled
uint8_t value_ctrl_reg3 = 0x40; // Interrupt activity 1 driven to INT1 pad
uint8_t value_ctrl_reg4 = 0x00; // FS = ±2 g,
uint8_t value_ctrl_reg5 = 0x08; // Interrupt 1 pin latched

Please suggest how can I get the accurate accelerometer readings.