Did your sealant freeze? I wouldn't have thought so, part of the formula is RV antifreeze. But you are riding outside my experience.

Was the puncture too big to seal? Do you have a plug kit? A guy on MTBR just posted a review of the Stan's Dart, which along with its mechanical function is coated with a catalyst for the sealant. He tried it with both Stan's and Orange Seal. With the Stan's it worked fine, the Orange Seal catalyzed but went powdery instead of gummy.

Had your sealant just dried out? This happened to me a lot on my first set of tires, which were not really tubeless tires (lacking the butyl inner layer) and they wept fluid. They worked better with Orange Seal than Trucker Co which I think is a Stan's clone. Stan's sells 2oz injector bottles with a valve remover molded into the lid.