Get an installments advancement by account ID and installments advancement ID.

This endpont generates an Installment advanced event.

Notes:

• Cancelling an installment advancement created with this endpoint does not generate a cancellation event. Pismo recommends that you use the most advanced version of the installment advancement endpoints instead:
  Create installment advancement
  Get installment advancement
  Cancel installment advancement
• This endpoint requires an account token - an access token encoded with a Pismo account ID. Tokens can expire quickly, which can result in a 401 Unauthorized message.