I pad Facebook group

( Co admin ) of Facebook group

re Chats and button for Chat

The button for Group Chats and access is fine on my IPhone 11, but the chat button and access does not appear on I pad Air (4)

Someone else accessed chat through desktop ( mine is new so basic; but can’t on it either ( seems that’s fon F book?) .

Messenger is fine .

How do I add that button? ( I’ve been on line for 20 min and have read Admin Assist.

Thanks for help!!