Worm Crisis

Had a major die off in my wormery.
Ive followed every instruction to the letter, but for some reason, about 75% of my worms have dived down into the sump and committed wormy suicide.
Contacted the wormery people, and they have been very helpful with advice.
I'll have to see if it recovers, or start again :-(

I wish I could find out why they died off. If it was the weather, then surely lots people would have had the same thing, and besides, I had mine wrapped in bubble wrap over the icy week we had.
It must have been something I put in, but I followed the list so very carefully.
Maybe Ill never know.
Very annoying....