There could be many different reasons:
The model does not offer this service. The models can choose to offer this service or not. Ask her to activate it to enjoy a VIP Show.
You are paying by telephone. The VIP Show option is only available if you have an account. You can create an account in a matter of seconds and then you can enjoy all our functions.
The model is already in a VIP Show session with someone else. You can continue watching her but you must wait until the current VIP Show session has ended to start your own session.