Are you talking about the Windows user name changing? If so, I don't see why you'd need to change anything IN jellyfin other than, maybe, file ownership.
Jellyfin 10.10.3 (Docker)
Ubuntu 24.04 LTS
Intel i3 12100
Intel Arc A380
OS drive - SK Hynix P41 1TB
Storage
3x WD Red Pro 6TB CMR in RAIDZ1 (JF Library)