HTTP Error 404 of authenticate API after upgrded the orchestrator version to v2018.2

we got a HTTP Error 404 from our developed website which asked a http request to authenticate API (https://IP/api/Account)
It has been worked fine over 6 months, but now we got this error after upgrded the orchestrator from v2017.1 to v2018.2.
That means, when we want to get the token from the authenticate API URL,
we get the message: ‘‘HTTP ERROR 404. The request resource is not found.’’ at our developed website.

We also try to use the tested API provided by consumer,
and successfully get the token by the same website code which just replaced by URL and Account.
(test API URL:

Even if we open the authenticate API URL in browser at our orchestrator machine,
we got the http error 405.

However, the authenticate API works well if we use the http request activities at UiPath Studio.

btw, we did not change the port of orchestrator, it used the port 443 as the same.

Could anyone help us fix this error?
This problem had caused all our RPA works from orchestrator over one week!!
It’s very Emergency!!
thank you!!

Thanks & Regards

did you resolve this? if yes how?