The redstone clock with a comparator doesn't work properly. Normally it would keep ongoing with its ticks, but now the redstone dust flashes but the output is not going on a continuous tick. It just activates one and that's it, it doesn't goes on forever.
Comments 2
Cleaning up old tickets: This ticket has not been updated recently (~1 year+) so is being closed as Cannot Reproduce. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines.
Quick Links:
📓 Issue Guidelines – 💬 Mojang Support – 📧 Suggestions – 📖 Minecraft Wiki
Did you set the comparator to subtraction mode? Maybe that's the problem. Can you please add a screenshot for clarity?