SYS_STATUS_RXSFDTO when range

Hi,
Now the range is work with the STM32l051 [email protected] clock frequency and 16MHz SPI baudrate, but it appears SYS_STATUS_RXSFDTO(0x04000000) at the rate of 3% in dwt_isr.
Who have encountered this question or know that how to solve the problem?

Thank you.
Best regards

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