While Cruz initially voted for Trade Promotion Authority (TPA), a bill that gives Obama fast-track trade authority when it came up for a vote in May 2015, he voted against the final passage in the Senate in June citing his disapproval with the “corruption” and “back room dealings” involved with the legislation. - See more at:
https://www.conservativereview.com/2016-presidential-candidates/candidates/ted-cruz#article-14
Ah, so Cruz can change positions on an issue, but Trump cannot? got it.