AFE4900: ECG signal debugging issues

Dear TI Teams,

One of our customer smart watch project is using AFE4900+SFH7072 for heart rate, blood oxygen and ECG detection. Their reported that there is high frequency interference when measuring ECG signals with fingers on the three electrode pads, and the ECG drawn from the raw data is messy.

The obtained ECG is as follows:

The schematic of AFE4900 is as below:

The testing equipment form is as follows:

1) They want to know how to implement filtering of ECG high frequency signals, i.e. filtering of raw data to extract useful signals.

2) Electrocardiogram drawing issue.

Can you give some suggestion for this case?

Thanks,

Kind Regards