Http Request Activity : Error Poxy -- Credentials are missing

I’m trying to use the HTTP Request from uipath studio to make a rest call to call a Web Service and collect XML datas. My GET call is giving this error (is working when you request direct from IE or Mozilla )

I put windows login and password in the properties panel but i’ve always the same error message.

Many thanks for your help !

Yes, we’ve met the same issue.
On the morning, the code works fine, but when we launch the same code in the afternoon, it pops up credentials are missing… please help