Whenever I try to open one of my PCs character or edit their character, it does not allow me to. in the campaign I have 7 PCs and this is the only one who is acting like this

Link: https://www.dndbeyond.com/profile/Kitsumie/characters/24083428

Again neither the view nor the edit pages will load even though I am the DM of the campaign they are in

I see a 404 error which could just mean the character is set to Private.

Can the player access the character themselves?

Have they made any changes to the character recently?

Yes, they are able to both access it and make changes