Why I'm getting an error on submission?

I am receiving errors when my people are submitting their forms?

 

I tested your form and I wasn't able to replicate this issue, the form submitted fine:

Could you please tell us more about the error you see when you submit?

We'll wait for your response.

Thank you!

One of my people here think it has something to do with our internal server. Will try it again later.
Thanks.
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