It may be that it was register Office, and no parish copy is available.
What other sites did you try?
(Give url).
Pauline
In future, also give the qtr, volume and page. You never know what can be done with thre information.
Marriage Locator Search Results
GRO Index: 1844 quarter 3, volume 12, page 506:
This marriage was at Ipswich St Margaret (RD: Ipswich).