It sometimes takes fish a while to get used to peas, but once they get the hang of it they usually yum them up! It does help if you fast them for 2-3 days beforehand though.
If fasting and peas don't cure the problem - and do give it 10 days at least - then the next step is to try an antibiotic food, such as Medigold or Metro-Med, which you can order online or by phone from the Goldfish Connection (www.goldfishconnection.com), as bacterial infection is another common cause. It may also help to increase the tank temp to about 78F.
Hope this helps.