illion BankStatements; Request fails if specifying a Referral Code or BrokerFlow Code with special characters

When specifying special characters in the illion BankStatements Referral Code or BrokerFlow Code request, you may encounter an error "Failed to Perform Bank Account Enquiry. Failed to execute Bank Account Request. Failed to execute illion BankStatements 'Request' request.".

The illion BankStatements service will return a HTML error page containing the text "The URI you submitted has disallowed characters".