Low-pass butterworth filter between 3-10 Hz with fs = 20000

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Hello I've been working to trying to design a butterworth lowpass iir filter with the designfilt function to and setting it to frequency instead of normalized. I'm not getting anything that may resemble filtered data I will provide the x and y variable so it may confirmed that it is not a data or sampling rate issue, fs = 20k.
here is step by step process of what I'm doing
1. butter_filt = designfilt %is preparing to design the filter
2. at the interface I specifiy Hz instead of normalized between 0 and 1 ( by the way I have tried normaling my pass and stop frequencies to the sampling rates and still get the same plots)
3. butter_data = filter(butter_filt, board_adc_data) The adc data will be provided at the botton
4. plot(t_board_adc, board_adc_data) this is plot of raw data
6. hold on
5. plot(t_board_adc,butter_data) this is plot the filted data
Do I need to use an FIR or a different filter type chevychev is one that comes to mind any help will be greatly apprciated I've been trying to figure out why this is not working for the last week and can't seem to find the answers, I'm very new to signals in my major so any help is welcome.

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