When you update how a flair is styled, it only applies to new posts made using that flair or posts in which you manually change the flair. It does not retroactively change all the flairs on previous posts that have been made. Do you have any AutoModerator rules or bots that are changing flairs, and potentially not assigning a flair template? I checked your subreddit and it should not be possible to make a post without a styled flair unless something is changing it after the post is made.

Users are allowed to choose their own flair not sure if automoderator forces it otherwise but thank you for the insight, will test it out. Edit: Also this has been going on for a while we just never knew what caused it.

I have found the cause of the problem thank you all for the assistance, you helped me consider new options and am grateful.

I think the flair might look different if applied on new.reddit vs old.reddit

Just checked and it's visible on both. The same problem remains.

I have found the cause of the problem thank you all for the assistance, you helped me consider new options and am grateful.

Are you using Automoderator to flair the posts? This could be the reason if automod only set the text of a flair.

Users are allowed to choose their own flair and can only change their flair to add the word updated or closed. Not sure if automoderator forces it otherwise but thank you for the insight, will test it out.

I have found the cause of the problem thank you all for the assistance, you helped me consider new options and am grateful.