Hello HandelshuysDoetinchem.

I'm sorry, but I couldn't replicate the issue from my side.

Here's how the plugin calculates when only one person books the appointment:

And when I make a reservation for 4 (1 + 3 additional persons), it looks like this:

So, the plugin does work as intended.

I believe the issue here is a simple misunderstanding.

You see, when you set the minimum capacity to be "4", it doesn't necessarily mean you will book for 4 people when you open the booking form, but instead you need to disable "Allow booking below minimum capacity" to be able to use it this way:

If these two sliders are enabled, your customers will be able to book an appointment below 4 and above 6 persons. And if you disable them, they wouldn't be able to book below 4 and above 6.

Best regards.