When creating a Token Request for AIS or PIS, you need to provide a value for the field `ref_id`.
After providing a value, if you receive an INVALID_ARGUMENT error with the reason Ref ID must be unique, this is because the value provided has already been provided previously.
In this case, please submit a new value and retry your request. If the new value is unique, your request should be successful.
If you continue to have problems after trying a new value, please get in touch with the support team and let us know, we can investigate this for you.