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When you choose Unlimited Choice, there is no limit to the number of answer choices that can be selected
How to change the number of Allowed Answer Choices
The number of Allowed Answer Choices for a Categories Category field is set on the Edit Contact Form page which where the Categories exists exist on.
This means that if the same Categories Category Field exists on multiple Contact Forms, it can have a different Allowed Answer Choices setting on each form.
Steps
Go to the Edit Contact Form page of the Contact Form that features the Categories Category field
There is a number in brackets to the right of the box containing each field. Press the number.
By default, it will say “1” to indicate that the Answer Choice setting is a single choice
If Limited multiple choice has already been set for that field, the number will be whatever limit has been set for the number Allowed Answer Choices
If Unlimited multiple choice has already been set for the field, the infinity symbol will be displayed: ∞
Pressing the number causes the Allowed Answer Choices popup to load
It presents three options:
Single Choice
Limited multiple choice
Unlimited multiple choice
Select the option you want to use on that Categories Category Field.
If you have selected Limited multiple choice, you must enter a number between 1 and the number of Answer choices available on that Categories Category
Press save to close the popup
Scroll to the bottom of the Edit Contact Form page and press Save.