Twitter's new payment-based model means feeds across the Internet are broken.
Last week, most (if not all) embedded Twitter feeds on sites globally ceased working. You've probably seen a lot of these messages as you make your way around the Internet.
There's a chance they may begin again, but as Twitter goes to a payment gateway model, where you have to be logged in to view Tweets, and can only view X number of Tweets per day, there will likely be a permanent change. We don't yet know what the end result will be, but changes are a-comin'.
While nothing is documented as of yet, even Twitter's publishing site doesn't work for their own dev account, you can view here:
https://publish.twitter.com/?query=https%3A%2F%2Ftwitter.com%2Ftwitterdev&widget=Timeline
So, what does all this mean for you? It means that your best bet is to hide your embedded Twitter timelines for the moment. You can replace that timeline with the standard 'View on Twitter' button, as that will still take users to view the account on Twitter itself. But remember that Twitter is requiring folks to log in now to view Tweets, so it's not a total fix.
We will keep monitoring this as developers and marketing folks across the world are figuring out what to do. As always, we've got your back.