UDP socket created In [InitializeOnLoad] won't cleanup after switching to Playmode

in a [InitializeOnLoad] static method I created a UDP socket, After Swithing to PlayMode ,this method will be trigger again;But this time it will report that the Port is In use ,So the second time will fail. My Tool works fine in Untiy2017,but won't work in Unity2021.3.17.
Why Untiy doesn't clean up all resource(here I mean sockets) I created in EditMode like it used to in 2017 version?
I guess it was because the Assembly reload problem ,So I tried to close my socket in AssemblyReloadEvents.beforeAssemblyReload event', sometimes it works, but after switching back and forth between editmode and play mode,the socket port just won't release ,So I can't start my socket any more. there is nothing I can do but restart Unity.FYI,I change to use different ports ,still the same result ,so I don't think it was my port number conflicting with other tools

Note: Testing was not done due to the issue not being reproducible by CQA