SASL not-authorized Error for Agent in Cisco Finesse XMPP Connection

[jazebsheraz05490]

I’m trying to connect to Cisco Finesse via XMPP over BOSH using Jabberwerx.js. One agent account is able to connect successfully, but another agent (which uses a UPN-style username) fails with a SASL not-authorized error.

Working Agent

This agent is able to log in and establish an XMPP connection:

• Username: QA2602

• Password: ********

• Extension: 1032

• JID Format Used: QA2602@uccx12-5p.ucce.ipcc

Failing Agent

This agent logs into the Finesse desktop just fine, but fails XMPP authentication via Jabberwerx:

• Username (UPN): NTT1@ucce.ipcc

• Password: ********

• Extension: 1021

I’ve tried the following JID formats in my XMPP connection:

• NTT1@ucce.ipcc@uccx12-5p.ucce.ipcc → Invalid due to double @

• NTT1%40ucce.ipcc@uccx12-5p.ucce.ipcc → Still fails with SASL not-authorized

• NTT1@ucce.ipcc → Fails with SASL not-authorized as well

The domain for both agents is: uccx12-5p.ucce.ipcc.

const config = {
    jabberUser: "NTT1%40ucce.ipcc@uccx12-5p.ucce.ipcc", // Escaped UPN username in JID
    jabberPass: "********",
    boshUrl: "https://uccx12-5p.ucce.ipcc:7443/http-bind/"
};

// REST API Login (to confirm credentials)
fetch("https://uccx12-5p.ucce.ipcc/finesse/api/User/NTT1@ucce.ipcc", {
    method: "GET",
    headers: {
        "Authorization": "Basic " + btoa("NTT1@ucce.ipcc:********"),
        "Accept": "application/xml"
    }
})
.then(response => {
    if (response.ok) {
        console.log(" REST API Login successful");

        // Start XMPP connection
        const client = new jabberwerx.Client("finesse");
        client.connect(
            config.jabberUser,
            config.jabberPass,
            {
                httpBindingURL: config.boshUrl,
                baseReconnectCountdown = 0;
                serviceDiscoveryEnabled: true,
            }
        );

        client.event("clientStatusChanged").bind(() => {
            console.log("XMPP Status:", client.status);
        });

    } else {
        console.error(" REST API login failed");
    }
});

Questions

1. Why does the UPN(User Principal Name) style agent (NTT1@ucce.ipcc) fail with a SASL not-authorized error in XMPP, despite logging in successfully on the Finesse desktop?

2. Is it valid to use a JID like NTT1@ucce.ipcc or does it require escaping to NTT1%40ucce.ipcc@<domain>?

Any kind of help would be beneficial for me. Thanks in advance . 
@cicso