This is the expected behavior of the form when compute mode is enabled. Users would be able to compute records and these records would show up in Airtable, but users will not be able to 'confirm' these records unless they click again to submit.

No formula can be calculated on miniExtensions Form itself without creating a record in Airtable first.

For more information about how formula fields work in miniExtensions form, please check out this page: https://miniextensions.com/formula-fields-in-miniextensions-form/