502: Error, {"error":"DocuSign send failed","detail":{"errorCode":"RECIPIENT_LIMIT_EXCEEDED","message":"The cumulative recipient limit has been exceeded."}}

I am working with a developer account and am receiving this error message:

502: Error, {"error":"DocuSign send failed","detail":{"errorCode":"RECIPIENT_LIMIT_EXCEEDED","message":"The cumulative recipient limit has been exceeded."}}

I tried deleting some envelopes but that did not resolve the issue. Our level of testing seems to be below the published threshold for a developer account.

Can DocuSign reset or clarify the cumulative recipient limit on a free developer/demo account? I have also seen reference to some kind of account hold that would result in the same error message. Any insights would be appreciated.