How do I make only of this field required such that they can only enter information on one state

Hello ​@Kemi 

Thank you for reaching out, and welcome to the Docusign Community! We appreciate your question and assure you that we are fully committed to providing you with the best service possible. 
I reproduced the issue and suggest you use the dropdown field and save it as a custom field instead.
Here’s how: 
1. Select the dropdown field from the left-hand panel.

2. Add the list of states under the options section by entering them as a list or a series in the right-hand panel.

3. Save the field as a custom field.

4. Place a single text box beside the dropdown as needed.

For your reference, click the article below.
Add Custom Fields to Standard Agreement Types

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Sincerely,

Ma. Cassandra | Docusign Community Moderator
If this helped, feel free to Like👍and click "Best Answer"

Hello ​@Kemi 

How are you? I'm checking in to see if you still need assistance. If yes, kindly reply here with more context or confirm if the issue has been resolved. 

If you run into any problems, we're happy to help with those here. Wishing you a smooth rest of your day!

If you found the response to be a useful solution to your question, please “like” and mark it as the best answer by clicking “Select as Best” to make it easier for other users to find. Thank you!

Sincerely,

Ma. Cassandra | Docusign Community Moderator

If this helped, feel free to Like👍and click "Best Answer"