AD9364 baseband digital filter design

We are using AD9364 in one of the project where we need to achieve around 58 - 60dB ACPR (Adjacent Channel Power Ratio) for 6MHz OFDM waveform with PAPR(Peak to Average Power Ratio) of 12dB. We are passing the input baseband samples to a mask filter whose output has 65dB ACPR in baseband. This filtered output is given to AD9364 input. 

We used ADI's MATLAB filter wizard to generate the FIR coefficients with the sampling rate of 6.912MSPS at the AD and base-band interface. At AD9364 Tx output, we are getting ACPR of 50dB only, irrespective of the Tx attenuation of 5 and 10dB. Now, we tried to increase the rejection in AD9364 filter by using the wizard. In wizard, it shows the rejection of 70dB at 3.1MHz away from the center frequency. But when we loaded those coefficients in the Evaluation board, we are getting a rejection of just 20dB at 3.1MHz away from center frequency.

Why are we seeing this mismatch between the filter response plot by MATLAB wizard and eval board response when loaded with the same coefficient?

Is there anyway to get 58dB ACPR in AD9364? 

We ensured that the input baseband signal has the ACPR of 65dB. 

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