Unique Question Field Not Working

I started to receive a few duplicate submissions rather than users editing their form. I have now enabled the setting to require a unique value for a field. I have just received another submission with the same value in the field. Could you please advise why?

Our apologies.

I checked the recent submissions in your form but I don't see duplicates. 

Can you provide the submission IDs with duplicate submissions?

May we also know if your form is embedded on your website? If yes, re-embed it using iframe embed code, this might help if there are issues.

Hi,
Please check MyNetball ID 3932414
Sincerely,
Ben Manfield
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Apologies for the inconveniences this may have caused to you. 

I have just checked your form and I can see it triggers properly the validation: 

I used the same value you provided "3932414", may be that the user sent the first submission before  you enabled the limit on your form. 

May you please test the same on your end and let us know if you can send duplicated values? 

Please let us know how it goes. 

Hi,

Thanks for responding promptly.

Would the setting not affect any records created before the Unique Question was applied?

No, I have tested this and the feature will only validate submissions after it was enabled. For example, it may be that you had already a value with 123 on the submissions when you decided to turn on the feature, then someone else submits 123, the submission will go through, but if someone tries to submit 123 again the validation will be triggered. 

Thanks Kevin for the clarification.
Cheers
Ben
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