Lin Yucong

iOS device failed handshake

1

**Describe the bug** I was able to connect using other devices includes android and windows but on one iOS device. It gave me a log that Handshake did not complete...

### What Happened? Hi, the custom_host in config providers does not work when given x-portkey-custom-host in request headers. All fallback providers tends to use the one given in x-portkey-custom-host instead...