Hello ​@MaxLeeds 

Thank you for reaching out, and a warm welcome to the Docusign Community! We are absolutely delighted to have you here and can't wait to share our knowledge with you.

I understand your concern about checkboxes where the Preview and the recipients can choose multiple choices when the Validation was set to "Exactly 1". I sincerely apologize for this, and rest assured that I will make my best effort to help you.

Upon checking, this behavior is by design and expected. The sender preview and recipient can select multiple checkboxes. However, the system will not allow to finish until the validation criteria are met, which means they need to untick some checkboxes until the validation criteria are met. The tooltip also shows the number of checkboxes they can/should select. If you want recipients to be only able to tick a single value, I recommend using the radio button instead of a checkbox, which will have the behavior you are looking for by default. 

Articles:

Field Types

Radio Buttons and Checkboxes: How and When to Use Each

I hope this is helpful to you. If you consider the response above useful, please click “Select as Best” to mark it as the “Best Answer .” This will assist other users with similar questions in finding it more easily.

Let us know if you need further assistance with this. Thank you!

Best regards,

Melanie | Docusign Community Moderator

"Select as Best" below if you find the answer a valid solution to your issue

Hello ​@MaxLeeds,

I trust all is well. If you found my response to be a useful solution to your question, could you please click the "Best Answer " button at the bottom of the post? It helps other community members who might have similar questions. Please let us know if you need further assistance. Thank you!

Best regards,

Melanie | Docusign Community Moderator

"Select as Best" below if you find the answer a valid solution to your issue