Nintex forms will do non-numeric validation for 'Currency' control by default. Are you doing any specific validation other than this. As of now we can't overwrite default validation messages in Nintex forms.

Thanks for the quick response. Yes, I am doing validation on the form to check that the value is numeric. So I get two messages displayed, the second being "The entered value should be a valid Currency", which is non-field specific. This is annoying when we are using tabs and the value is hidden as the user will not know which specific field is being referred to.

only way would be not to use currency data type but rather simple string and perform all the validations on your own.

Have you reported it to Nintex? I would like also to change message to non-english validation message.