docusignapi - Docusign UserId changing after envelope is created -

i'm using docusign rest api create envelopes, call post recipient view method generate recipient view.

the documentation indicates:

you can use userid or email , username identify recipient. if userid used , clientuserid provided, userid must match recipientid (which can retrieved recipients call) envelope.

i know sure username can change if user types different full name when adopting signature, i'm favoring userid. suggested in documentation call recipients right after creating envelope, , store userid guids.

later, when recipient ready sign , call post recipient view send userid saved earlier , clientuserid (because it's embedded recipient). of times works, error:

{ "errorcode": "invalid_request_parameter", "message": "the request contained @ least 1 invalid parameter. value not found parameter 'username'." } 

when happened first time called recipients failed envelope , noticed userid captured when envelope created doesn't match current userid.

my workaround call recpients, current userid, , call post recipient view again. that's not ideal.

questions/comments:

• is userid changing during lifetime of envelope?
• what's best practice obtain proper userid? after creating envelope? right before creating recipient view?
• it great if api returned userids in response coming when creating envelope.