When doing what?
Did you check all the webhooks/entries in the Get EventSub Subscriptions endpoint? Reference | Twitch Developers as a “dead/invalid/broken” entry will sit in the lsit for about 10 days.
So you might only be looking at page 1 of results from this endpoint and need to check other pages if a cursor is present?
Also note, every time you restart ngrok it’ll assign a new URL (on the free plant at least)