I doubt this is related to your issue, but I will mention this otherwise. I have just recently purchased a few units but haven’t done anything RF related just yet.
The XIAO ESP32C6 features an RF switch for selecting between the onboard antenna and the external RF port. The switch has two GPIO used for enabling the RF switch and selecting the RF output. These can be seen in the schematic - Page 5 section B2
XIAO ESP32 C6.pdf (seeedstudio.com)
I am not sure if these are switched ‘automatically’, but something to keep in mind if you have communication/reception issues. Also try assigning a static IP address and see if that helps.