Custom Date Formats Not Saving

So I have tried the stable and beta version but for some reason the date display settings custom format does not save. It used to work on my site for like 2 years and now it has stopped. I tried updating the format but when I go back to view my display settiing changes nothing is saved. Then when I do it in views it saved but does not output correctly. For example I use the custom format n/t/Y and it doesn't save or it outputs as n/t/7 - t instead of what I put. I really just want to use one of the other formats default to drupal but they have the time on them. I don't want the time to display if that makes sense.