Aducm355 EIS Problem with 0.1-1 kHz. Bad result for low frequencies

im using M355_ECSns_EIS code example.
I want to take a measurement with freq. sweep. Unfortunately for low freq. the result is not as expected.
I guess the reason for the wrong result is that the measurement is done too quickly. I tried to change parameters such as ImpODR but it didn't work.
I need exact results for low freq. band and help how can i fix it in code.
Thanks in advance for your help.

Here example with RC circuit. 1kOhm, 1uF