Why is my Twitch stream not showing up on VERGR?

Usually it is one of these: Twitch is not connected (or needs reconnecting), you are not actually live on Twitch yet, or VERGR has not detected the stream yet. VERGR checks for your Twitch broadcast on a short cycle, so it can take a couple of minutes to appear after you go live, and to clear after you stop.

The Twitch mirror shows your Twitch broadcast on VERGR automatically, so when it is not appearing, it is almost always a connection or a timing thing. Run through this and it usually sorts itself.

Check these in order

Confirm Twitch is connected in Settings, Linked Accounts. If it has been a while, reconnect it.
Confirm you are actually live on Twitch right now (the mirror only shows a live Twitch broadcast).
Give it a couple of minutes. VERGR detects your Twitch stream on a short polling cycle, so it is not instant.
If it still does not appear, disconnect and reconnect Twitch to refresh the access VERGR uses to detect your stream.

Common causes

Twitch not connected, or the connection expired: reconnect in Settings, Linked Accounts.
Not live on Twitch yet: the mirror only surfaces an active Twitch broadcast.
Detection delay: there is a short, normal lag between going live on Twitch and the stream showing on VERGR.
Just stopped on Twitch: the VERGR mirror also takes a couple of minutes to clear after you end.

The mirror direction is Twitch to VERGR: you stream on Twitch and VERGR surfaces it. You do not stream to VERGR for the mirror, so nothing changes in OBS.

It appeared but then would not go away after I stopped.

The mirror ends on the same short cycle it starts on, so a finished stream can linger for a couple of minutes before VERGR marks it ended.

It worked before and now it does not.

Your Twitch connection most likely lapsed. Reconnect Twitch in Settings, Linked Accounts and the mirror resumes.

My chat is not bridging either.

That points to the same expired Twitch connection. Reconnecting restores both the mirror and the two-way chat.