Unfortunately, that's not possible. Formulas cannot call an API on their own, this would have to be triggered by either a user clicking a button or via Pipelines, based on the save action. What you're wanting to do cannot be done with a button click alone, so you will need to utilize Pipelines and your process will probably be something like this:
- User adds/edits a record and inputs the Registration Number
- User saves the record
- Pipelines is triggered based on Add/Modify action where [rego] has been changed
- Pipelines calls the API
- Pipelines updates the record from the trigger action based on information received from the API call
With your Pipelines setup, you will probably have to use some of the JSON steps since you need to call an API and act on the response. Hopefully, others can assist you with that part as I have not utilized those features in Pipelines.
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Blake Harrison
bharrison@datablender.io
DataBlender - Quickbase Solution Provider
Atlanta GA
404.800.1702 /
http://datablender.io/------------------------------