Limit number of bookable events?

Hi there.

I am trying your plugin which seems great!
My idea is to make a tennis court available for any users to book per hour.

So I created a calendar with one activity per hour and 12 activities a day.
But I want to prevent a user to book for more than one hour (activity) per day.
I tried to group events but it didn’t help.

Any idea is welcome.

Thanks.

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