Hi Liam, thank you for contributing to the 8x8 Community.
From the error message you are receiving 407 (Authentication Error) this originates from incorrect 3rd party credentials used.
From the screenshot attached, we can see the User must be the GUN SIP (Most likely); however, the Password appears to be 5 characters long, which may not be the correct one, judging from the error message received
I'd recommend ensuring the User and Password are correct, as the Authentication Failure pinpoints this as the culprit.
If you are still experiencing issues after verifying that you are using the correct credentials, please do not hesitate to contact our Support Team.
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Alison Stewart
8x8
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