Breaking out of each of the inner loops after 1 trial should work – expect conditions will be selected at random each loop of the outer loop, rather than avoiding conditions already used.
To do what I think you want, you could preload the conditions into lists before the outer loop and then just have the outer loop. Have a look at the Brookes template experiment Is it possible to randomize image order, but repeat that specific randomized order during a loop? - #12 by mtruong