TXS0104E: Normal communication

Hi:

I use the level conversion chip of TI, there are some problems in the operation, please help to answer, thank you.

My application:

Module UART through TXS0104E to TXS0108E, through the serial port conversion chip to PC

Problems:

In the test, sometimes the communication is normal, sometimes there is a garbled code

I would like to ask, in the middle of the two level conversion chip, how to ensure normal communication, also please give some advice.