Issues with payments processing when user already has a current subscription?

Hi,

Received an alert about errors with the payments processing. From looking at the process payments notification logs, it seems to all be the same error:

2012-11-16 01:34:53,966 - process-payment-notifications - INFO - Processing 1 subscriptions left in intermediate states.
2012-11-16 01:34:54,928 - sca.utilities - ERROR - Error while using LP API call getArchiveSubscriptionURL.
Traceback (most recent call last):
  File "/srv/sc.ubuntu.com/production/software-center-agent/src/softwarecenteragent/utilities.py", line 392, in create_private_deb_line
    subscriber=subscriber)
  File "/usr/lib/pymodules/python2.6/lazr/restfulclient/resource.py", line 527, in __call__
    url, in_representation, http_method, extra_headers=extra_headers)
  File "/usr/lib/pymodules/python2.6/lazr/restfulclient/_browser.py", line 306, in _request
    raise HTTPError(response, content)
HTTPError: HTTP Error 400: Bad Request
Response headers:
---
connection: close
content-length: 61
content-type: text/plain
date: Fri, 16 Nov 2012 01:34:54 GMT
server: zope.server.http (HTTP)
status: 400
strict-transport-security: max-age=2592000
vary: Accept,Accept-Encoding
via: 1.1 api.launchpad.net
x-content-type-options: nosniff
x-frame-options: SAMEORIGIN
x-lazr-notifications: []
x-powered-by: Zope (www.zope.org), Python (www.python.org)
x-xss-protection: 1; mode=block
---
Response body:
---
KL Wong already has a current subscription for 'Eufloria HD'.
---

2012-11-16 01:34:54,929 - sca.models - INFO - subscription (id: 498264) by https://login.ubuntu.com/+id/xxx for Eufloria HD ($50000.00): PaymentAuthorized -> PaymentAuthorized: 3 failed attempts: HTTP Error 400: Bad Request
2012-11-16 01:34:54,948 - process-payment-notifications - INFO - Processed subscription id=498264 - subscription (id: 498264) by https://login.ubuntu.com/+id/F6KDr8h for Eufloria HD ($50000.00). End state: PaymentAuthorized

Could someone please take a look into this?

Thanks,

Haw