How to have the text error message hidden but still have indicator that there is error

Perhaps as a feature request the values can be hidden so that the text still displays the error indicating that a valid number has not been entered without hinting what the value is?

Hi,

The error message is somewhat a way to inform users about the actual error, hiding it may not really be a feasible feature. However, you can edit form warnings by following this guide: https://www.jotform.com/help/61-How-to-Change-Form-Warnings. 

If the goal is to simply hide the error message of a specific field, this can be done by injecting custom CSS codes, and we'll be glad to assist you on that. I believe my colleague, Kiran, has already provided you a CSS code that works? 

Also, I'm not sure why you are using minimum and maximum value for vouchers? Are your vouchers specific, similar to coupon codes? Or they are simply numbers and does not really need validation? If I may suggest, using the Input Mask option would also be a good alternative: https://www.jotform.com/help/381-Getting-Started-with-the-basics-of-Input-Masking. 

I hope that helps.