Mine was a multi hour troubleshoot tied back to a failing power supply. 3 yulinca 10G switches in series, vlans across them that started passing traffic outside their own vlan intermittently. As well, intermittent loss of some main vlan traffic. The intermittent aspect made it the toughest to troubleshoot. Also, after a reboot of a switch, the middle one would spend a lot of time hunting to set the speeds. Absolute failures easy to troubleshoot. This was a puzzle that chatgpt actually solved, proposing a power supply failure. I thought impossible but nothing else made sense. Replaced it and to my surprise, solved it.