Unable to add children to booking

I am struggling with setting this up. On all of the tours I have created I can only add adults from the drop down booking list. I can select children but can’t add them. Age restriction has been set to ‘any’ and prices have been added to the age groups.

My next problem is if I select adults it takes me to my basket and it says my basket is empty.

I have deactivated all plugins to see if there is a conflict but I still have the problem.

What am I missing?

Many thanks

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