Handle the indexerror exception on create_order

LMS-2646
ALWAYS use named variables in your i18n'd strings. Translators may move these strings around and it may break how you do string substitutions! https://github.com/edx/edx-platform/blob/master/docs/en_us/developers/source/i18n.rst#use-named-placeholders

```python
please contact us at {email_address}".format(
email_address='<a href="mailto:{technical_email}">{technical_email}</a>'.format(technical_email=TECH_SUPPORT_EMAIL)
)}
```