The cold temperature caused the active to fall out of suspension and crystalize. No need to refrigerate your Exem.
Store RC liquids (non-peptides) at room temperature in dark, low humidity environments.
Things that may help: run the bottle under some hot water - heat up some water in a dish in the microwave and then add the RC to the hot water for a minute or two.
Topical AAS can also get cloudy or crystalize when subjected to cold temperatures. Partial submersion in warm/hot water helps.
The product will work fine. If there are any crystals left in the bottle when the liquid is gone, add some warm water, swish it around and get yourself an extra dose or two out of the bottle.