Weird I usually only put already read never puted "want to read "idk that is weird try to long out and long in again or something I hope it work for u
Try clearing the cashe on your browser and restarting your phone, if you're on one
Could be a temperory problem.. bc some ppl even thousands of mangas marked as read n all.. it shows that mangago probably doesnt have a cap for for marking mangas as reading/already read/want to read.. you can try logging out n back in.. if it doesnt work just wait it out or notify them.. sometimes stuff like this happens bc the mangago team keeps upgrading their website... hope your issue gets resolved..
Uh Maybe it’s just me but when i try to add a manga to “want to read” no matter how many times i click it, it doesn’t work so i tried to delete some off my list but i cant do that either so the already read, want to red, or reading buttons don’t work for me lmao anybody got a solution?