I sent my first nocturnal, lighted nock through a doe on Sat. Morning. As fast as that arrow passed through her Im amazed that any blood can get in the tiny hole that allows the user to turn them off but somehow blood gets in there and you can’t get it out. What are other guys doing? Are you putting a small piece of tape over the hole to keep the blood out or just not worrying about it. Has anybody had a nock stop working because of fluids?

I have shot but a single deer with a lighted nock and it is still functioning. Once the ones I have are dead or ruined I will not purchase additional unless i perceive an advantage which I did not on the first deer.

DIY put a bit of peroxide on it to get the blood out. I normally rinse mine out immediately with water that I always carry in my pack.
Just thinking as I type this but another thing that might help is apply some Vaseline to the hole to keep the juices out. Or maybe even some Scent Away or Dead Down Wind deodorant. Its soft enough to go in but should not interfere with getting something in to turn it off.
I like the Nockturnals over all the others I've tried.