If it's any consolation, I felt exactly the same when I came across that phrase the first time.
In the following challenge as well. I thought I'd never be able to say that one.
A few days later, things started to fall into place and I now find it quite a bit easier to say than at first.
So your tongue may un-twist itself eventually as well after you've heard it several times, and repeated it as best you could each time!