Wireless network issues with tx2

The TX2 board is unstable and frequently disconnected after connecting to WiFi, and the detected WiFi signal is very weak. May I ask where there may be a problem with the settings? This board has just upgraded the 18.04 system on the official website. Thank you in advance for your kind help.
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There is no update from you for a period, assuming this is not an issue any more.
Hence we are closing this topic. If need further support, please open a new one.
Thanks

Sorry for the late response.
Is this still an issue to support? Any result can be shared?