Encountering the list numbers being incorrect yet again.

It's been a while since I last encountered this issue and now it has happened again. I was just updating the list order when all of a sudden after clicking save list order, it said that they have encountered an error which made the list numbers being incorrect with some numbers doubling or being skipped. Maybe it's the website or my device that is causing the issue. Anyway, I hope this gets fixed soon. Link to the list: Action Movies and Action Elements - IMDb