Hi, sadly it is normal. Immigration process is slow, complex and confusing.
E-request for typographical error is not applicable in your case based on my understanding. You submit e-request about typographical error in this case:
1) You received EAD with wrong information
2) Wrong information is caused by USCIS mistake
Source:
https://www.uscis.gov/green-card/green-card-processes-and-procedures/employment-authorization-document
In your case, you don't have EAD and mistake was on you.
So I would just file a new case with new fee with correct information and withdraw wrongly filed I-765 for renewal. However, considering how long you are into adjustment process, you may never see your EAD and get GC before that.
It is not USCIS responsibility to give you legal advice or tell you what and how to do. Tier 1 officers on chat or phone simply need to give you some reply to get you off line and go to next person. The more people they reply, and less time they spend, the better it looks for their performance. So they will tell you anything.