Hey Twitter, I Tried Ads and Here’s What Happened

I’ve read mixed reviews on Twitter Advertising. Not having used it myself, I thought it might be worth giving a shot. I’d like to attract some more folks to the Marketing Technology Twitter account and I wanted to see whether some ads would help. I guess I don’t get to find out.
Hey @TwitterAds, I tried to spend money with you but you wouldn’t let me
I carefully navigated the filtering options to narrow down my audience. I selected Marketing as a category, put some keywords from our categories to target, and even provided a couple dozen other user accounts to try to attract their followers as well.
When I completed the targeting, I was offered the opportunity to select one of my Tweets, or build my own. I chose to make my own. Again… I spent some considerable time crafting a message to test and a nice image for it.
And then I tried to publish the Twitter Card… notice the error:

Grrr…
No problem, I say to myself. I saw that there’s a save button to save your campaign on the top right. So, I click save and… notice the error:

I have absolutely no idea what to do now. I can’t save all of the work I did targeting the campaign and can’t save all the work I did on the creative.