I need a support agent to release an Instagram connection

Hi, I own the Instagram account @kovira.tech (display name "Kovira").
When I try to connect it to ManyChat I get "Kovira already connected to
Kerem OLGUN," but I cannot access that account. I re-authorized via Meta
and still hit this wall, so the permission side is fine — it's a stale
connection on ManyChat's side. I have NO ManyChat account via Facebook,
Apple, or Telegram, and my Google account (keremm.olgun@gmail.com) is
empty with no channel. Please release/disconnect this Instagram account
from the old "Kerem OLGUN" account so I can connect it to
keremm.olgun@gmail.com. I can verify ownership of the Instagram account.
Thanks.