[Jiaz]

Yes, it's not hard to understand but as I cannot reproduce the issue, I need more information to either reproduce this myself or with help of some logs from you to see what is going on.

1.) what proxy software do you use, so I can setup my own test setup? danted/squid...?
2.) what proxy mode do you use? Socks4/Socks5/Http/Https?
3.) do you enter
3.1.) dns name with
3.1.1.) AAAA record
or
3.1.2.) AAAA and A record?
or
3.2.) IPv6 in full notation, with [] or without []?
or
3.3.) IPv6 in short notation , with [] or without []?

Thanks for your help and time with this issue