New subscription managed by the administrator

Hello !
Normally, the administrator can create a new subscription. Every time that a new member subscribe by a postal mail for example, it's the administrator who makes the subscription.
I don't know what it appened, but I am no more able to do the subscription or the membership. I only can make the subscription to a new plan for a person who is already a subscriber.
Here is attached the photo of what I see on the screen. It lacks many data about the person.
Sincerely,
Christian