I tried to make a Redstone elevator with a automatic door closing and opening when the elevator comes. So I tried of using cauldrons sticking with slime block which would go up and down. I added a comparator for detecting the cauldron but when the cauldron moved by a slime block machine the comparator still would give Redstone when the outputs taken from a block, until it is being updated by breaking a block or diverting Redstone signal

Note:- I tried to restart Minecraft 2-3 times but still didn't fix, assuming as a bug I reported.