Can’t pin some friends as #1 BFF in SnapChat Plus - what to do?

i'm just going here through snapchat and if i tap on some people i can see that i can pin them as a bff and i have snapchat plus subscription so i'm using that feature but for some other people i don't see that and then i don't know uh so for some reason maybe i just sent them friend requests they didn't accept yet or something like that or because yeah for some people i see this option for other people i don't see it um i don't know why some people i can't pin them as number one bff was the issues there or something or what's the reason if you have any other insights just let me know of course i understand that you need to be a snapchat plus subscriber and all of that i'm just curious to understand why for some friends this feature is not working